Roma Aeterna

12th – 13th Saeculum AUC (5th Century AD): Various groups of Central Asian nomads unify in a vast confederation and make a massive breakout in Eastern Europe, overrunning and devastating its border provinces and making inroads as far as Gallia and Italy. The effort to contain the nomad invaders absorbs the empire’s energies for the rest of the century, and forces it to shelve any plans for an all-out effort to conquer the Sassanid Empire. However, by now Rome has the internal stability and military resources to reduce the nomad breakout to a huge, very taxing, decades-long but manageable security problem, instead of an insurmountable existential threat. The improved cavalry and archery developed in the Persian wars allow the legions, who have maintained their excellent infantry quality, to be an effective match for nomad breakouts. Eventually the Roman legions defeat and repel the invaders, using combined arms tactics for heavy cavalry and archers. The conflict leads to Roman annexation of the Bosporus kingdom and a strip of territory in Eastern Europe up to the Neman-Horyn-Southern Bug line.

Rome undergoes the construction of an extensive fortification system on the new Eastern border (the “Great Limes”) which effectively becomes an equivalent of China's Great Wall. To be accurate, this is but the first version of the Great Limes. In the following centuries, as the Empire gradually expands eastward in the steppes, the Romans build new fortification systems on the current borders, typically using some river system as basis. The old limes typically gets at least partially dismantled to enable free movement of trade and troops and allow an extension of the road and canal system. However portions of it may be often kept as a secondary defense system if the primary one gets breached.

In the aftermath of the nomads’ onslaught, Eastern Europe experiences a few sizable demographic changes: several Germanic and Slavic peoples are pushed in Sarmatia to mingle with Baltic, Finnish, and Iranian tribes, while several others are allowed to settle in the empire on the Romans’ terms to help (re)populate the old and new border provinces. Romanization and development of Arabia proceeds apace. Hostilities with Persia cool down for a while as that empire is also suffering a major series of attacks by steppe nomads on its northern border. Aksum invades Nubia and Arabia, and makes inroads in Egypt. The Aksumite invaders are eventually pushed back when the nomad onslaught cools down and Rome can redeploy more forces to Africa. In the aftermath of the conflict Rome annexes the northern coast of Axum, re-establishes the rest of the border on the western outskirts of the Ethiopian Highlands, and consolidates it with new fortifications. The Romans however are too exhausted to seriously contemplate a total conquest of Aksum.

The Romanist religion spreads to become the faith of the majority of the Roman Empire's population in the West and the plurality in the East. A kind of informal religious leadership for Romanism is gradually established both as a subset of the civil service and a body of scholars that combine expertise in classical literature (especially as relevant to mythology), law, philosophy, and religious ritual. Gradually the body of lore expected from Romanist scholars grows to include logic, mathematics, and empirical expertise in medicine and natural philosophy as well. Romanist scholars undergo a vast effort to organize an extensive corpus of Greco-Roman literature and philosophy relevant to Romanism, and to integrate it with the compiled oral literature from other traditions within the empire, such as the Celtic, Germanic, and Slavic cultures. Mystery cults largely fall in obscurity as the vast majority of their following is absorbed by Romanism.

Middle Eastern monotheistic and dualistic religions (Christianity, Manichaeism, Zoroastrianism) steadily keep losing influence, following, and sympathies within the Empire, as many Roman citizens come to see such “alien” religions as a distasteful, unwholesome, and troublesome expression of disloyalty to Roman culture. The Emperors and the Senate heavily tax and heap legal penalties on followers of religions who refuse to give allegiance to Rome and the Emperor in Romanist ceremonies.

The Roman authorities create a system of state-supported charities, initially to care for the victims of the nomad invasion, but later expanded across the empire as the basis of the Roman philanthropic system. It helps lessen social unrest and reduce the appeal of the Christian community’s welfare system.

Spurred by ongoing population growth in the Roman Empire, the "Roman Agricultural Revolution" takes off. Roman traders and explorers travel across most of the Old World, and establish an early global economy across most of Asia, vast portions of Africa, and all of Europe. Their trade networks extending from the Atlantic Ocean and Mediterranean Sea in the west to the Indian Ocean and China Sea in the east. The global economy established by Roman traders across the Old World enables the diffusion of many crops and farming techniques among different parts of the Roman world, as well as the adaptation of crops and techniques from and to regions beyond the Roman world. Hundreds of new crops are diffused throughout Roman lands as a result of the Roman Agricultural Revolution. They include rye, sugar cane, rice, citrus fruit, apricots, bananas, coconut palms, cotton, aubergines, saffron, lemons, sour oranges, eggplants, limes, almonds, figs, sorghum, mangos, artichokes, spinach, carrots, hard wheat, colocasia, plantains, and watermelons.

The Romans start developing a scientific approach to agriculture based on three major elements: sophisticated systems of crop rotation, where land is cropped four or more times in a two-year period; highly developed irrigation techniques, using machines such as norias, water mills, water raising machines, dams and reservoirs, which allow to greatly expand the exploitable land area; and the introduction of a large variety of crops which are studied and catalogued according to the season, type of land and amount of water they require. Roman travelers successfully smuggle silkworm eggs into the Roman Empire, which leads to the establishment of an indigenous Roman silk industry.

Technological progress continues, with the diffusion of many numerous innovative industrial uses of water mills, early industrial uses of tidal power, wind power, and fossil fuels such as petroleum, and the earliest large factory complexes. A variety of industrial mills are invented in the Roman world, including fulling mills, gristmills, hullers, paper mills, sawmills, ship mills, stamp mills, steel mills, sugar mills, tide mills, and windmills. Roman engineers also invent crankshafts, connecting rods, and water turbines, first employ gears in mills and water-raising machines, and pioneer the use of dams as a source of water power, used to provide additional power to watermills and water-raising machines.

Rural slavery changes as well as a result of the economic and legal changes: unfree latifundia rural laborers become more akin to serfs than chattel slaves. They are granted more personal rights, but their freedom of movement is still restricted. They live in estate enclosed villages, forming a network of sub-communities, that are managed by a freedman steward. He worked his way to his position and lives in a bigger house than his former kind, who either live in huts or in slave-barracks. Records are kept on slave families, individuals, and their relations and they are sometimes moved around the estate, or traded to other estates, to prevent inbreeding. Every now and then, children from the slave families may be collected by servants of the landlord to become either new household staff, or perform seasonal work on the lord’s villa/manor. Gifted or surplus children may be sold on through the market system, and enter the urban household slavery system, where they are given to professionals as slave-apprentices, or given as rewards to the landlord's social clients. Slaves from beyond the empire serve alongside condemned criminals in dangerous or exhausting occupations, such as mining, quarrying, civil engineering, the most lethal forms of gladiator games, or forced prostitution.

Educational institutions for legal practitioners begin to transform under the influence of Romanist scholarship into a full-fledged higher education system as they provide education into other subjects. Their curriculum grows to include law, medicine, philosophy, Romanist classics, mathematics, grammar, rhetoric, logic, astronomy, accounting, architecture/engineering, and natural philosophy.

13th – 14th Century AUC (6th Century AD): A renewed major effort by Rome to conquer the Sassanid Empire hits the latter in a moment of serious weakness due to an ongoing civil war caused by dynastic strife. This leads to Roman conquest and annexation of eastern Persia and Khorasan. The region however remains a hotbed of rebellion and strife due to its Zoroastrian character, increasingly hostile attitude of Roman culture to Middle Eastern monotheist religions, and frequent raids and invasions of steppe nomad and Iranian peoples from Central Asia. Roman intolerance to monotheism also leads to a renewed row of Jewish rebellions that the Legions quash. The Empire also faces and successfully repels the encroachment in southern Sarmatia of another steppe nomad confederation. Roman legions are able to use the military tactics they have mastered in the previous century to very good effect. The new nomad threat increases the interest of the Imperial government to develop the Sarmatian border provinces as a strong frontier bulwark. A recurring series of border clashes with Aksum entrenches the border on the northern and western outskirts of the Ethiopian Highlands.

As it happened with Aksum, border contact with Rome fosters demographic, cultural, economic, and technological development in the Norse of Scandinavia and the various peoples of Sarmatia, as well as their political progression from the tribal level to increasingly bigger and more organized polities.

The Empire engages in a major effort is started to connect the border territories in western Sarmatia to the Roman road and canal system and foster their settlement. The canal system is gradually expanded to link with the Neman, Horyn-Prypiat, and Southern Bug rivers. After several centuries of settlement and development, Northern Europe has essentially reached the level of Western Europe in population and economic development, and in combination both areas make for a second heartland of the empire that matches the Mediterranean lands in importance. By now, Arabia is more or less as Roman in character as Syria, Egypt, Mesopotamia, or Media. Plague hits again the Empire, stopping Roman expansion in Asia as ambitious plans for an invasion of India are shelved. The plague heightens interest for medicine and natural philosophy in Roman culture.

Many industries are generated due to the Roman Agricultural Revolution, including the earliest industries for agribusiness, astronomical instruments, ceramics, chemicals, distillation technologies, clocks, glass, mechanical hydro-powered and wind-powered machinery, matting, mosaics, pulp and paper industry, perfumery, petroleum, pharmaceuticals, rope-making, shipping, shipbuilding, silk, sugar, textiles, weapons, and the mining of minerals such as sulfur, ammonia, lead and iron. The first large factory complexes are built for many of these industries. The Roman domestic water system is improved, with the development of a widespread network of sewers, public baths, drinking fountains, piped drinking water supplies, and widespread private and public toilet and bathing facilities in all cities.

Two types of economic systems are developing in parallel in the Roman world. Command economy and politically-driven investment by the government bureaucracy and military, most prominent in newly-acquired and far-off provinces, prompts agricultural development and colonization of under-exploited lands, typically combining the settlement of veterans and colonists in state colonies and in individual land grants, and cares for building and extension of the road network, the canal network in Europe, and the irrigation system in the Middle East, as well as the establishment of an extensive postal system. At the same time, the first market economy and earliest forms of merchant capitalism, most prominent in the Mediterranean provinces, but also briskly expanding to Britannia, Gallia, Hispania, and Germania, take root. A vigorous monetary economy is created on the basis of the expanding levels of circulation of a stable high-value currency (the denarius). Its effects include market-driven agricultural development with the spread of advice, education, and free seeds, introduction of high value crops or animals to areas where they were previously unknown, development of an extensive international trade network, and widespread manufacturing.

Innovative new business techniques and forms of business organization are introduced by economists, merchants and traders during this time. Such innovations include the earliest trading companies, big businesses, contracts, bills of exchange, long-distance international trade, the first forms of limited partnerships, issuing of insurance, and the earliest forms of credit, debt, profit, loss, capital, capital accumulation, circulating capital, capital expenditure, revenue, cheques, promissory notes, trusts and charitable trusts, startup companies, savings accounts, transactional accounts, pawning, loaning, exchange rates, bankers, money changers, ledgers, deposits, assignments, the double-entry bookkeeping system, and lawsuits.

As an effect of economic, legal, and technological changes, slavery undergoes a gradual decline and marginalization process in Roman society as the agricultural sector becomes increasingly reliant on tenant farmers and urban economy on free laborers, artisans, and craftsmen. Unfree labor mostly tends to survive as a combination of various systems: evolution of rural slavery into serfdom, in the areas where tenant farming does not become prevalent; temporary indenture or apprenticeship for the training of skilled labor; and chattel slavery as a form of punishment and exploitation of convicted criminals and defeated enemies and rebels. The latter is typically prevalent in dangerous and exhausting occupations such as the mines, quarries, public works, or forced prostitution. This process may sometimes be significantly slowed or even temporarily reversed when events such as military victories, conquest of new territories, and repression of rebellions cause a temporary increase of availability of new slaves, but it always reasserts in the end.

Technological progress steadily continues in the Roman world: new technologies that spread in the Empire include buttons, mirrors, rat traps, spectacles, spinning wheels, magnets, compass, counterweight trebuchets, astrolabes, rib vault, coffee, hang glider, hard soap, shampoo, nitric acid, alembic, valve, reciprocating, combination lock, quilting, pointed arch, and surgical catgut.

The formalized higher education system spreads throughout the Roman Empire and takes the shape of an informal “university” system as they develop an effective accreditation system through letters of commendation. Teachers write those for promising students, and one collects a series of them from a number of senior philosophers, doctors, architects, jurists, or other kinds of experts until one is effectively recognized as an established scholar. This gets official support by Imperial authority as the letters of commendation become a preferential title of merit for civil service recruitment and getting appointments in some branches of the military. Certain branches of the civil service are accredited as the senior ranks of the commendation system (e.g. as jurisconsults of imperial authority or archiatroi). The students of the great institutions where the most accredited masters cluster become the academic elite, while the majority of accredited scholars walk out of provincial schools with letters of commendation detailing what they learned and from who.

The development of the “university” system, supported by Romanist culture, spurs a heightened empiric interest into logic, mathematics, natural philosophy, and medicine: notable scientific advances in the second half of the first millennium include the first definitions of the scientific method, development of a decimal place value number system and the zero, systematization of arithmetic and algebra, solution of linear and quadratic equations, and those polynomials of higher degree that could be reduced to quadratics through substitution, first developments in differential calculus, the theory of impetus, first integrated systematization of mechanics, optics and hydrodynamics, development of chemistry, rediscovery of atomism, advances in trigonometry with the definition of the trigonometric functions, advances in surgery with the standardization of surgical instruments, development of a mathematical scale to quantify the strength of drugs, a system that would allow a doctor to determine in advance the most critical days of a patient's illness, introduction of systematic experimentation and quantification into the study of physiology, discovery of the contagious nature of infectious diseases, introduction of quarantine to limit the spread of contagious diseases, and development of experimental medicine and clinical trials.

So far, the dominant method of indentifying Roman years was to name the consuls that held office that year (during the Republic) or using the regnal year of the Emperor (during the Empire). Now Romanist scholars standardize the Ab Urbe Condita (AUC) dating system, which numbers years since the founding of Rome, traditionally dated to 753 BC. Endorsement by the Imperial government popularizes the use of the epoch and spreads its use throughout the Roman Empire, leading to its widespread acceptance. Romanist scholars also standardize the duration of a saeculum (length of time conventionally held roughly equal to the potential lifetime of a person, used by Roman historians to periodize chronicles and track major events) to a century.

Monotheistic religions have been marginalized to a tiny fringe by Romanism in the West, and reduced to a minority in the Middle East, except eastern Persia and Khorasan. The Christian, Jewish, and Zoroastrian communities stage several riots and uprisings against the unfair tax burden and legal penalties that these minorities suffer. The Emperors and the Senate retaliate by harsh military repression and enforcing even more penalties in the form of unfavorable property and inheritance codes for these religious minorities. This further accelerates the sharp decline of monotheism across the Middle East. Zoroastrianism only remains widespread in the Khorasan region due to its recent conquest by Rome. The Jew community also remains significant due to its close-knit community support system, but it is increasingly marginalized and alienated from Roman society.

Increased trade and cultural exchanges with India due to conquest of the Sassanid Empire allow an expanded diffusion of Hinduism and Buddhism to Rome, where they are welcomed much more favorably than Middle Eastern monotheism due to their perceived affinities with Romanism. Over time, Hinduism is mostly subsumed in Romanism, while Buddhism remains distinct.

14th – 15th Saeculum AUC (7th Century AD): The Roman Empire gradually recovers from the effects of the plague. However, a nasty dynastic crisis evolves in a political one, and eventually causes a civil war and the breakdown of the Roman Empire in several warring fragments. A combination of rebellion and invasion in eastern Persia allows the region to break away from Roman control. By the end of the century, clashes between the various breakaway Roman states lead to their consolidation into a Western Roman Empire and an Eastern Roman Empire. This reflects the West-East division that tends to surface within the Roman polity in times of strife, and is a analogue to the North-South division that is likely to occur during similar periods in Imperial China. A parallel period of internecine strife in the Aksumite Empire however grants Rome some peace on its southern border.

The Norse peoples of Scandinavia begin their 'Viking Age' of raids, trade, warfare, exploration, and settlement. For Rome the most noticeable effect is the appearance of a new threat: the Norsemen, so far deemed not really worth the effort of conquest by the Roman ruling elite, start to seriously harass the Roman world with frequent raids on towns laying on the coasts and along the rivers of Europe. As a rule, however, the Romans are able to prevent any permanent conquest or large-scale settlement (on the invaders' terms, anyway) of their territory by Viking raiders.

Things are different in Sarmatia, where Scandinavian ('Varangian') adventurers, traders, pirates, and settlers penetrate the region in depth and in sizable numbers through the Dnieper and Volga trade routes. They end up considerably influencing and accelerating ongoing growth into one civilization of the mélange of Germanic, Slavic, Finnish, Baltic, Turkic, and Iranian peoples that inhabit the northern woodlands and southern plains of Sarmatia. Thanks to Varangian influence and demographic changes in the region during the 5th-6th centuries, the prevailing ethnic-linguistic character of the nascent Gothic polity becomes a Germanic one, with a secondary Slavic influence.

Renewed uprisings by Jews, Christians, and Zoroastrians are quelled by the Romans with large-scale brutal repression, enslavement, and deportation. This effectively wipes out these communities as a recognizable element in the Roman population. Survivors are mostly expelled beyond the borders of the empire. Only the breakaway status of eastern Persia allows Zoroastrianism to keep a foothold in this region. Religious dissidence otherwise dies out in the Roman Empire: even the surviving elements of the Manichean community convert to Romanism or Buddhism or flee to escape the unfavorable Roman tax and property regime. Division of the Roman Empire does not stop persecution of monotheists since it is one issue pretty much all factions can agree upon.

By the end of this century Romanism has become the faith of the vast majority of the population in the Roman Empire. However, Buddhism continues its diffusion in the Roman world, as civil strife drives many people to doubt the values of Romanism and seek a different source of spiritual solace. Its growth gets much more tolerance than monotheism, since it is mostly perceived as not hostile and dangerous to Roman civilization.

Notable technological developments of this period include the hourglass, mechanical clocks, dry compass, cross-staff, mariner's astrolabe, stern-mounted rudder, arch bridge, steel crossbow, and oil paint. Chinese alchemists discover gunpowder.

Despite the very good quality that the Roman road and canal system has achieved, the vast extension of the Empire and the huge amount of trade between its different areas and with the Asian civilizations spur the interest of the army, civil service, and private traders for ways to make sea and land transport and communication more reliable and efficient.

Nice timeline, always like reading about a surviving Rome.

Modern Roman culture values useful service to society, the pursue of happiness in prosperity, stoicism in adversity, unity and strength of the state, individual success in a stable society, freedom and diversity in law and order, meritocracy, industriousness, militarism, imperialism, useful innovations, and traditions that stood the test of time. Romans consider an ideal member of their civilization to be a perfect blend of martial and intellectual prowess. If in doubt, it is advisable to err on the side of the martial, or at least knowledge with practical application, for those who take too philosophical or artistic a path risk being branded as weak and a burden to society. Even so, a cultured Roman is expected to be able to appreciate art, music, and poetry, and to converse knowledgeably on a range of subjects from politics and history to science and engineering. Romans are also expected to have strong wills, strong stomachs, and to have their nerves steeled for battle or adversity. A level-headed and practical approach is regarded almost as highly as courage or education; the Roman mind excels in tackling practical problems in order to solve them and pursuing theoretical knowledge to understand and control the world.

The language of modern Rome is a “Roman” hybrid of Latin and Greek based on Latin script, much the same way English arose from a fusion of Old English and Norman French. Historically there was a cultural divide between Latin West and Greek East; in modern times, however, public education ensured pretty much all Imperial citizens spoke both languages, so the difference grew meaningless. Widespread bilingualism and influence of mass media eventually caused Latin and Greek to merge into an Imperial mixed language. For the same reasons, geographical divergence of Roman is contained to the level of recognizable but minor variations in different regions. Other languages of regional importance were historically spoken in the lands of the Empire but are largely extinct or used by tiny minorities in modern times, and only keep academic relevance. Roman language includes many borrowings from other historical and living languages.

Over time, pressure of industrialization and a wish to keep social peace led to development of a welfare system as the evolution of a long-standing tradition of state charities and private patronage system. Much the same way Roman society gradually marginalized and abolished slavery outside of its criminal justice system, achieved equal rights and social status for women, and developed general acceptance of sexual freedom and reproductive rights for both sexes. However Roman culture celebrates masculine traits, albeit tempered by teamwork, discipline, and responsibility, does not suffer them to be threatened, and scorns feminine traits outside of a few important but specific fields such as childrearing, nurturing of the sick, romantic relationships, and heterosexual sex.

So it came to accept social equality of women by developing a ‘Spartan’ or ‘Amazonian’ ideal that women can and should be as tough, resourceful, and assertive as men and so deserve equal rights and status. It loathes the notion that men or society at large should be allowed to become too gentle, empathic, or sensitive. The ideal Roman woman should be girly when in exclusive female company or in the fields where feminine traits are valued, and a tomboy in all other situations. Therefore women (and everyone else, really) are expected to deal with bullying or unwelcome sexual or seductive behaviour that do not involve violence, coercion, or gross abuse of authority with their own resources without bothering society for protection.

Rape by physical force, coercion, or abuse of authority however is acknowledged as a most serious crime and rapists that are caught may look forward to many years of harsh penal labor if they are lucky. There is general acceptance of sexual freedom for both genders. Respectable Romans are expected to seek pleasure and happiness but show discretion, clear-mindedness, and self-discipline in matters of sex and appetites and bear the consequences of their behaviour stoically. Widespread use of adoption for Imperial succession, to secure an offspring in case of infertility, and to form alliances between families led Roman culture to deemphasize the importance of legitimacy.

There is plenty of tolerance for homosexual behaviour; Roman culture mostly seems to ignore the notion of exclusive sexual orientation and treats bisexuality as the expected norm. However effeminacy is quite a serious taboo in Roman society, so there is very strong prejudice against males that are effeminate, show too much preference for passive homosexual behavior, or indulge in cross-dressing. For similar reasons there would be very little tolerance for an hypothetical radical feminist critique of Roman society. Within these boundaries, Romans are entirely accepting of homosexual behaviour and women's equality. Due to social preference for bisexuality and responsible hedonism, Roman art and popular culture do include a lot of sexual objectification of attractive people but do so in roughly equal amounts and intensity for both genders. As a rule, Romans have little interest or patience for ascetism or prudery that exceed their own notions of propriety.

Slavery has been abolished with the exception of convicted felons for the duration of their sentence. All slaves in the Empire are property of the state that may rent them to privates. If they escape execution, enslaved convicts may be sent to forced labour in dangerous and back-breaking occupations or forced prostitution in state brothels, used for medical experimentation or in the most lethal forms of the gladiator games, drafted in penal units of the army, or otherwise ruthlessly exploited by society to make up for their crimes as circumstances dictate.

Imperial justice is swift and severe. As a rule, murder, treason, espionage, and wartime desertion carry the death penalty. Manslaughter, rape, robbery, disloyalty to the empire, and peacetime desertion are punished by enslavement for a period of between ten years to life. Crimes of lesser severity are punishable by either fines or a set number of watches of hard labor or community service. Mitigating and aggravating circumstances apply; recidivism carries sharply increased sentences, up to and including life enslavement or execution. The principle of restitution applies; a person convicted of inflicting harm to another’s property is expected to make it good, plus pay for the cost of his trial. In the Empire incarceration is not a punishment. Jails exist, but they are only used to hold those undergoing questioning or those awaiting trial.

Enslaved criminals have to hope to survive their sentence without permanent disability or get a pardon, which is frequently granted to meritorious convicts. On the other hand, recidivist or unreformed felons may often be worked to death by penal labour or executed right away. Suicide is usually accepted as a way to atone even the most heinous crimes and failures. Romans also frequently use it or state-assisted euthanasia as an approved way to escape incurable infirmity or intolerable adversity. Children born with serious disabilities are seen as an intolerable burden to themselves, their families, and society. Widespread use of prenatal testing and abortion ensures most foetuses with important disabilities and genetic diseases are identified and eliminated before term, and the rest is usually euthanized.

Imperial Rome has “Romanism” as its majority religion and national faith. It is a religion broadly similar to Hinduism that combines a synthesis of Indo-European and Near-Eastern polytheist religions with strong pantheistic and monist elements borrowed from Stoicism, Epicureanism, Buddhism, and Hinduism. There are also sizable minorities that are adherents of Buddhism, embrace secular humanism, or less frequently practice other South Asian or East Asian religions; they enjoy full tolerance. On the other hand, Rome has a legacy of overwhelming prejudice against Middle Eastern monotheist religions. In the past it came to regard them as destructive threats to its security when they became a rallying focus for violent social or proto-nationalist unrest. This includes Christianity that historically embraced militancy with riots, uprisings, and sectarian violence in the face of persecution. Rome toiled long and hard but was eventually successful in the effort to destroy Christianity, Judaism, and Zoroastrianism within its territory and expel their remnants beyond its borders.

Pretty much the same way, Rome also wiped out those religions and cultural practices it met in its colonial expansion and perceived as harmful, barbaric, and an affront to civilization, such as the Amerindian and African cultures that practiced human sacrifice or genital mutilation. As a persistent rule throughout its history, Rome does show full tolerance of those cultures and religions it perceives as valuable or at least harmless. It zealously and efficiently strives to repress and destroy the ones that are deemed a threat to society. The latter was the fate of various new religious movements and cults that historically arose in Roman territory, were deemed too troublesome or dangerous, and ruthlessly suppressed.

Modern Romans in abstract have a very negative opinion of aggressive monotheism and religious fundamentalism but in practice concern and animosity faded over time to a distant page of Roman history since they are essentially perceived as an extinct or negligible threat in the modern world. Hypothetically speaking, however, a revival of, and confrontation with, militant fundamentalism would likely give new life to dormant Roman prejudice. If the Empire were to be threatened by something like religious terrorism, one may expect the Romans to do their best to kill or enslave anyone within their reach that looks like a supporter or sympathizer. The Romans would also likely perceive a fundamentalist state with important conventional military resources or worse WMD capability as an existential threat, especially if it had the means to threaten Roman territory or interests.

Modern Roman society keeps its traditional strong appetite for violent sports. However nowadays most gladiators are highly-paid, respectable, and admired professional athletes; there is also a minority of convicted felons that try to survive the most lethal variants of the games and hopefully earn a pardon. Modern gladiatorial games mostly include human vs. human fights or various kinds of dangerous stunts; overuse of mega-fauna in human vs. beast fights in the past put several species in endangered status, leading to severe limitations to their use. Nowadays all 'wild' animals that are still used in gladiatorial games are expressly bred in captivity or in the wild in controlled conditions, sometimes with the help of artificial insemination.

Bloody fights to the death have all but disappeared except in the case of convict vs. convict matches. There are still occasional fights with real weapons and bloodshed in professional matches, but deaths are rare. Most gladiators are expensively trained professionals and quite valuable, so defeated fighters are never killed and all are trained to disable rather than kill. Most gladiatorial combat is fought with heavy armor and blunted melee weapons or alternatively martial arts, either in individual matches or team bouts; last man or side standing wins. Also common are team bouts resembling full contact capture-the-flag. Injuries are common and an accepted part of the sport. The big exception to lack of lethality is convict fights, which are treated as an entertaining form of execution and risking one's life in exchange for a chance at earning a pardon.

Great thread so far if i mind say so.

I'm thankful my humble efforts met your approval. Of course I gladly welcome constructive comments and questions. One issue I was quite uncertain to write about and wondering if my guesswork seriously underestimated likely ATL reality is the size and structure of the modern Roman army. Simply put, there is no OTL state, past or present, that comes remotely close to TTL Rome in population, industrial power, or resources, which obviously influence military power. Only adequate analogue would perhaps be if NATO+EU+Russia would merge in a single state. To put things in perspective, modern Rome's borders may vary from an absolute minimum of Europe (including Russia), North Africa, Middle East, the Horn of Africa, and a varying portion of Siberia and Central Asia to a likely maximum of that plus (most of) the Americas, East Africa, Southern Africa, India, and a varying portion of Australia. All areas of Roman territory are heavily populated and industrialized except the Artic regions and those desert areas that weren't made more hospitable with macro-engineering. The main deciding factors about size variance of modern Roman Empire are how many colonies Rome is able to keep for all time instead of losing them to equivalents of the Atlantic Revolutions supported by rival empires, which areas get colonized by each Eurasian superpower, how contested border areas get settled in the end according to military and diplomatic butterflies, and if India is able to resist Roman conquest by timely imperial unification.  

Never mind. On second thoughts, I realized 2010s-equivalent modern Rome actually may well be more technologically advanced than OTL across the board, not just in energy, space, and biological technologies, thanks to its greater amount of brainpower and resources, as well as its pro-science attitude. It may well show similar improvements in cybernetics, IT, nanotechnology, and materials science, to quote but a few typical fields. I did not think of or explictly write about them because I have lesser familiarity with potential advances in these fields and I'm fairly sure OTL cutting-edge modernity failed to realize its full potential in space, energy, and biological technologies for various reasons. I'm less sure about other fields.

Let me correct you there and state flat out that the "Dark Ages" were a myth created by Renesiance thinkers who saw themselves as bringing light and progress to Europe. Yes, Europa suffered greatly from Rome's collapse (to put it in modern perspective, imagine if the power and water had suddenly been cut off) and much progress was lost. But sceintific Development did not grind to a halt and progress was made in various fields. Alchemy for example, was the predecessor to modern day chemistry and far Ahead of what the Romans ever developed.