One of the most fascinating texts (in my opinion) from the corpus of early medieval Irish literature is In Cath Catharda - a free adaption of Lucian's Pharsalia, which is a poetic retelling of the civil war between Julius Caesar and Gnaeius Pompey. It was actually one of the most popular texts in medieval Ireland because of its riveting battle scenes, rousing speeches and scenes of magic, fantastical creatures and phenomena. It's interesting in this context because the Irish author of the text tries to convey to the reader - in a medieval Irish context - the institutions of the Roman republic.

Early medieval Ireland was a more or less stateless society where political relations and socio-economic hierarchies were pretty much conflated. Lords had clients who they call up to war not on the basis of their institutional subordination, but because they had entered economic and social contracts with them and this was a consequence of their obligations to that contract. So instead of X office being subordinate to Y office because it was prescribed by law, warriors were subordinate to their lords and kings on personal basis.

On top of that, Ireland had a plethora of kings whose status depended on the number of clients they held beneath them. Legal texts describe a situation where local kings of a single territory were subordinate to regional kings who held several lesser kings beneath them, who were themselves subordinate to a provincial king who claimed nominal rulership over one of Ireland's 5 historic provinces (Mide, Leinster, Connacht, Ulster and Munster).

This translates into the author of In Cath Catharda's explanation of Roman political offices:

The royal Roman dominion had a beginning in manner different from those of the high dominions aforesaid; for not at all with overkings did Rome's supremacy abide. But whenever it was desirable, the chiefs of the senate, together with men of rank and honourable degrees, gave orders to levy their tribute for them from foreign races, and to invade the several tribes of the world, to rule and to guide the royal Roman right.

Now Decanus was the appellation of the lowest of those ranks. He was chief of ten: he was the man who used to punish every theft and robbery and outrage that was committed amidst the City.

Centurio above the Decanus: chief of a hundred was that man.

Tribunus above the Centurio: chief of two hundred or three hundred was he.

Vicarius above the Tribunus: that man used to assume the function of the Comes when the Comes would go to converse with the king.

Comes above the Vicarius: chief of one city was he.

Tóissech ('chieftain') above the Comes: twelve cities were subject to him.

Patricius above the Tóissech; the righthand man of a King or Emperor; and this was his work, to pass judgments and decrees instead of the overlord when the king himself was weary.

King above the Patricius: three tribes were his domain.

Emperor above the King. Howbeit the Romans had not that rank until Julius Caesar took it by dint of his hand, as the tale hereafter will tell. The Emperor, now, was overlord of the world above everyone, and there was no one superior to him.

There were, moreover, two grades, the rank of Consul and the rank of Dictator. Now the Consul had (only) one year in his rank, and at the end of the year he was changed lest he should become proud or arrogant from the strength of his power and the height of his rank. If it happened that during that year he prospered in his consulate he was re-appointed to the same rank by the will of the senate and the finding of the people. Junius Brutus was the first to obtain that rank among the Romans. Now the Dictator, whether he did well or ill, was not changed from his rank till the end of five years. If then everyone was thankful for him, he was not changed at all. Wherefore that rank is the most esteemed that they had, until an Emperor's might rested upon them.

Thus then the Roman realm extended and spread out to the four airts of the world, so that pride and glory grew thereout in the Romans, and vast quarrels and civil warfare arose among some of those nobles in the provinces wherein they dwelt outside throughout the world, and others in Rome itself in the midst, for the greatness of their pride, and because of the exceeding great power which they had acquired over the nations and kindreds of the globe.

For the space of two-hundred-and-fifty-three years the royal dominion of the Romans remained in that wise, without an Emperor, without a monarch over them, but the men of diverse ranks directing their government. Until once upon a time, by decision of the senate and by advice of the people, (a Dictator) was made by them, for the dictatorship is the one rank they had that is noblest and most honorable.

So there's two possibilities here: either that the author, who lived in an intensely monarchic and aristocratic society, could not conceive of leadership as anything but aristocratic and personal as in Ireland; or that he was doing his own version of the interpretatio Romano on Roman political institutions himself in order to explain them to his audience who themselves couldn't understand the very concept of republican government. Needless to say, the author is basically just imposing the Irish conception of kingship as a pyramid of kings depending on their subjects that I described above onto the political offices of the Roman state.

Personally I think it's the former because of his acknowledgement of "kings" as a status in the system of government is contradicted by his statement that the Emperor or monarch was a later development. In any case, this extract from the text demonstrates that readers and possibly writers in the medieval Irish world had to understand the republican government of the Roman state in their own terms - as a hierarchical system of kingship depending on the number of one's personal clients. I also think that the text is interesting in a cultural way; it acknowledges the Roman emperor as rightful ruler of the earth coming from a society that had never been under Roman rule, which can actually be seen in later medieval Irish annals that list the coronations and deaths of the Eastern Roman Empire as momentous occasions. It goes to show how the influence of the Roman Empire extended far beyond its borders, and how the elites of non-Roman societies that bordered it actually thought that Rome was pretty sweet and awesome.