Space Romans

""A heavily industrialized 20th century-type planet very much like Earth; an amazing example of Hodgkin's Law of Parallel Planet Development. But on this Earth, Rome never fell.""

- Captain's Log, stardate 4040.7 (Star Trek: The Original Series "Bread and Circuses")

A sort of three-way cross between Fantasy Counterpart Culture, Inexplicable Cultural Ties, and Planet of Hats, a Space Roman society is a human or Human Alien culture that, in an amazing coincidence, resembles a culture from Earth's history. This trope does not exclusively describe only those based on Rome, but any implausibly Earth-like society. Space Romans provide a handy way for the beleaguered writer to populate the galaxy with a variety of different, believable alien societies, but disbelief can easily be stretched to its limit if the writer isn't careful, or doesn't consider how the culture in question would be altered by being transplanted to space.

An inoffensive version of Space Jews. See also United Space of America. Contrast with Culture Chop Suey.

Two common variants are the Space Amish, a society of technological dropouts, and the Space Cossacks, rebels and/or exiles from mainstream society.

Anime and Manga

 * The Galactic Empire in Legend of the Galactic Heroes is very German (more specifically, Prussian) in its style and influences. Some fans meanwhile call the Free Planets Alliance "Space Americans."

Comic Books

 * In DC Comics the Daxamites have recently been established as being "Space Mexicans". The human-like natives of the planet Daxam had a distinctly Mesoamerican racial appearance and culture. They were colonized by the pseudo-European Kryptonians, with whom they subsequently interbred and established a distinct culture, including things such as buildings resembling step pyramids. When the Kryptonian's intergalactic empire collapsed, the Daxamites became independent. They now exhibit some attributes of being Space Amish. While they have and use advanced technology, they are very isolationist to the point of xenophobia and have strong cultural taboos against certain technologies, such as anything related to space travel.
 * The Wolrog Empire in Strontium Dog is modeled on pre-World War II Japan. The entire thing is ruled by a single Emperor who the rest of the people obey immediately and without question. Captives are regularly press-ganged into becoming soldiers and slaves to fuel the war effort. They also readily utilise kamikaze tactics; to participate in one of these is seen as the greatest honour that can be obtained.

Film

 * Star Wars' presentation of a republic falling and giving way to empire has obvious parallels with Rome; the Republic Senate gets a vote of no confidence, and Chancellor Palpatine becomes Emperor by popular acclaim. Alas, his acclaim came from a False-Flag Operation, he failed to deliver on his campaign promises, he was actually a Sith Lord, and he ended up a 0% Approval Rating Big Bad to the setting.

Literature

 * Given the ambiguity of whether it should be considered science fiction or fantasy, it's hard to tell if examples from Dragaera fit here or under Fantasy Counterpart Culture (perhaps both). In particular, there are the Fenarians, seemingly the dominant group of human culture, who speak Hungarian and have various Hungarian cultural traditions. More generally, Dragaera has a marked similarity to late medieval Europe, although given that supposedly the "Dragaerans" were genetically engineered from humans, there is likely some kind of Days of Future Past scenario going on.
 * Arkonides of Perry Rhodan' being mixture of predominately roman and british imperialism making them sort of albino Centauri.
 * The Empire in Isaac Asimov's Foundation series of novels is very, very Roman by design. Asimov was inspired to write the Foundation series as a parallel to Gibbons's The Decline and Fall of the Roman Empire.
 * To wit, it starts out as the Kingdom Trantor, then is for some time the Republic of Trantor, and later becomes the Galactic Empire. In its decline, it even gets its own Belisarius stand-in, Bel Riose.
 * The entire world of Markerterion in Stationery Voyagers is occupied by characters with Spanish-sounding names. Every location on Markerterion looks to be either the Sahara, Spain, Mexico, California, Louisiana, or Kalamazoo. Little to no explanation is offered on how this happened. Your Mileage May Vary on whether or not the California-like region's inhabitants qualify as Space Jews.
 * The Abh Empire in Crest of the Stars are an aversion: a Tall, Dark and Snarky Feudal Future fond of Luxury Tropes and good living in general, but enthusiastic conquerors, largely indifferent to their conquered peoples, and well able to knock you into next week. They kind of resemble the French, but not quite: pre-Revolutionary France wasn't all that good at warfare and oppressed its peasantry, while Revolutionary France was revolutionary (the Abh are not known for their guillotines), and Napoleon was hardly feudal.
 * If anything they come of as subtly alien in something akin to the Uncanny Valley but entirely through the mannerisms which appears deliberate and rather well thought out. This is justified of course since well they are aliens but were originally bio-engineered humans created by humans and used for space travel making them some of the Blue and Orange Morality disposition. One character even notes that while they're very respectable, honorable and kind to those they conquer he can't trust them because they're just too alien. Ironically his justification is derived from human cynicism and the acceptance that Humans Are the Real Monsters thus the fact these aliens are not bastards squicks him out.
 * A couple of examples in the Vorkosigan Saga: Barrayarans are Space Ruritanians; Komarrans are Space Venetian Merchants; the planet Athos is made up solely of men, everyone is gay, and reproduction is done through science - as the name suggests, they are like futuristic Ancient Greeks; Beta Colony is Space Freestate Amsterdam, although with a lot of Blue State America as well.
 * Ascended Fanfic is in play here, as the author describes the first version of Cordellia's honor she was working on for her Fanzine being with the Barrayarans as Klingons and Beta Colony as The Federation. Over time she's considered Beta Colony to be mostly American descended, but with the culture being firmly Californian. Most of the rest of the countries have listed their group of colonists, although the Jackson's Whole is closest to a standard pirate state mixed with corporate state.
 * Take a wild guess at what the British Space Empire resembles in Space Captain Smith
 * Tour of the Merrimack explicitly has Space Romans who were descended from the original ones. They survived as a secret society in America before breaking off to form their own colony.
 * In the Tomorrow War series by Alexander Zorich, some extrasolar human colonies were hit by a weird effect nicknamed "retroactive evolution", which makes people en masse fall back to knowledge and behaviour stereotypes of some or other ancient people, presumably ancestors of the majority of them - without forgetting enough of their own to get blown from FTL era into early Iron Age. Between travels and post-scarcity "Now What?" retrospection, Earth itself ended up affected, but weakly and haphazardly, so it only got mild retraux flavours here and there.
 * The first such throwback was Zoroastrian Persia, which promptly renamed the planet Khosrov, broke off United Nations and began a rapid expansion of its own as independent Concordia. They are very determined, orderly and and loyal to their theocracy, in their own way honorable and intensely use cloning to beef up their numbers. Neither constitues very good news for United Nations that turned into locally custmoizable One World Order with rather corrupt major players. While mostly "Zoroastrianism ethics is not the worst thing in the world at all" indeed, the flavour of theology that emerged from their growth phase includes decrying nonhumans for hellish beasts, which isn't good news for aliens (especially pre-FTL ones), nor Concordians themselves (especially when some aliens happen to be cyborg hive whose fighter sized warrior caste has grown-in gravitics and lasers). They also came pre-infiltrated with resurrected Manichean heresy - which isn't good news for anyone at all (these guys occasionally pull stunts like ).

Live Action TV

 * The Romulans from Star Trek; heck, their homeworlds are even named Romulus and Remus, their politicians are Senators and Praetors, and their soldiers are Centurions and Legions.
 * Explained in some potentially cannonically source or another as being the result of Sufficiently Advanced Aliens having formed the basis for the Roman pantheon and culture and those same aliens doing the EXACT SAME THING with the Romulans. The Romulans just took to it better/with better technology.
 * It does raise the question as to where THOSE aliens first got the whole Togas and Senators and Bowl Cuts and Empire ideas from to begin with.
 * Star Trek even had actual Roman space Romans in the original series, complete with slaves and gladiators, as well as 1920s Chicago Gangsters, Native Americans, Nazis, the Yangs (Yanks) and Kohms (Commies) of "The Omega Glory", and even an exact duplicate of Earth in "Miri".
 * The Yangs even had their own Constitution with the EXACT SAME WORDING and an old flag identical to the 50 starred US flag.
 * The 1920s Chicago Gangsters averts the amazing coincidence part of this trope: the entire reason why the Enterprise is there is to attempt to fix the cultural contamination that happened the last time the Federation sent a ship to the planet. As it turns out, that cultural contamination consisted of leaving a book about the mobs of Chicago in the 1920s in the hands of a highly imitative culture... the Nazis, similarly were a direct consequence of someone's meddling (a mad historian deciding to use the Nazi model to uplift a primitive civilization), rather than the species just happening to develop Nazis on their own.
 * Similarly to the Chicago Gangsters in TOS, Star Trek: Enterprise has an entire planet whose inhabitants look straight out of the Wild West. It turns out that they're actually the descendants of 19th Century American pioneers abducted by aliens...who proceed to defeat said aliens, trash their technology and reduce them into being second-class citizens.
 * Such cultures appear over and over again in Stargate SG-1. Most of them were transported by the Goa'uld from Earth, making them descendants of the actual peoples they resemble.
 * The Centauri Republic from Babylon 5 can be described as a blend of the Roman Empire with 18th-19th Century Europe, right down to their fashions, aesthetics and government. Despite being a Vestigial Empire that's at times mocked for decadence however, the Centauri are shown to be very dangerous opponents if one gets on their bad side.

Tabletop Games

 * Warhammer 40000 does this all the time, though in weird mixes.
 * The Imperium of Man is the unholy fruit of a foursome between ancient Rome, medieval Prussia, Nazi Germany, and the Inquisition-era Catholic Church, complete with Byzantine double headed Eagles, the Iron Cross, the Inquisition, Enormous Cathedrals, the God-Emperor, Latin. They aren't called Catholic Space Nazis for nothing.
 * Within the Imperium itself, various Space Marine homeworlds seem to each have their own Earth counterpart: The Space Wolves are Norse / Russian, the Ultramarines are Classical Grecoroman, the White Scars are Mongol. Thousand Sons had an Egyptian theme going on, the Word Bearers took after the three monolithic religions of the Middle East, and Emperor's Children had something resembling French and Italian high culture before they were corrupted by Chaos.
 * More obvious in the Imperial Guard: The Valhallans, Praetorians, Catachan,Death Korps of Krieg, Attilans, Armageddon and others all descendants or counterparts of Earth culture.
 * Taoist Space Communists? The Tau.
 * The Eldar are at times Japanese Space Greeks, but show elements of being Space Tuatha Dé Danann.
 * More minorly, the Orkz are a species of green British football hooligans, replacing enthusiasm for football as the reason for collectively sowing chaos with just loving violence.
 * The Necrons began as the Tomb Kings In Space, which in turn are the Theme Park Version of Ancient Egypt.
 * The Third Imperium in Traveller is a lot like The British Empire Recycled in Space especially in the noble classes. However in some aspects of culture it also resembles a United Space of America.
 * Justifiable by assuming that much of it was a deliberate Shout-Out to tradition.

Video Games

 * The turians of Mass Effect are basically this. They possess the most powerful navy in the (known) galaxy, they're notoriously high-strung, they obsess over honor and they generally go about "keeping the peace" (Pax Turiana anyone?).
 * They even have their units organized into legions, with records of their deeds for each one. In fact, some records go back to the Turian iron age!
 * Their name makes it all the more obvious: (Cen)turians!
 * Not only that, there's:
 * 27 strict tiers of citizenship. The first is basic citizenship; children and client races. The second? Mandatory military service. The third is formal citizenship attained after leaving boot camp. Which starts at the equivalent of the child's 15th birthday. And so on and so forth...
 * Client races (like the volus) as compared to the Romans' client kingdoms (independently ruled kingdoms, except for international affairs and they must pay tribute to Rome).
 * Ridiculous militarization. This is very noticeable because the turians have had to almost fully take over 'peacekeeping' duties from the formerly cooperative krogan, who are now too few and too disorganized to be useful in such a capacity.
 * They jump at any perceived issue as a reason for war (the First Contact War for the turians, pretty much every war ever for the Romans, but particularly things like the Second Punic War, started after the Romans perceived the Carthaginians' expansion into Spain as a threat).
 * Even their names are very often Roman sounding. "General Septimus", anyone? Or Hell, even "Garrus Vakarian" has a Latin ring to it.
 * For some reason, the Terrans in Starcraft are dead ringers for the Confederate States of America; Southern accents, Black laborers, powerful "Old Families," a strange mix of redneck and gentlemenly mannerisms, and even the title of "Confederacy." Oh, and they have the same flag. According to the manual, they are the descendants of humans exiled from Earth because they had the potential to develop psychic powers, which were the political scapegoat of choice at the time; and they apparently developed a bad case of Future Imperfect.
 * For some reason, the Terrans in Starcraft are dead ringers for the Confederate States of America; Southern accents, Black laborers, powerful "Old Families," a strange mix of redneck and gentlemenly mannerisms, and even the title of "Confederacy." Oh, and they have the same flag. According to the manual, they are the descendants of humans exiled from Earth because they had the potential to develop psychic powers, which were the political scapegoat of choice at the time; and they apparently developed a bad case of Future Imperfect.

Web Comics

 * The Dhuvalians of My Life at War have a very French feel to them in their names and mannerisms. Additionally the Free Market feel a lot like the American south.

Western Animation

 * The Superfriends was fond of this trope. Planets they visited included Camelon, the medieval planet; Zaghdad, the Arabian Knights planet; and Texacana, the cowboy planet.
 * One episode of Futurama featured this as in inversion of Ancient Astronauts: an alien culture was an exact copy of Ancient Egypt because they learned about pyramid construction and space travel from the Ancient Egyptians.