fwiw, the indigenous people of the crimean peninsula were a proto-iranic (proto-slavic) group that the greeks called the tauri, three proto-iranian groups called cimmerians, scythians and sarmatians, in sequence, and probably peasant slavic groups first identified by herodotus as scythian farmers. slavic is a weird language. it is a satem language, making it more similar to iranian than to german in some ways. herodotus indicates the ukraine had a peasant class of farmers and a ruling class of mounted warriors and they were slightly different ethnic groups. it has long been thought that the slavs were there the whole time, as the underclass to the iranians, but that it was not well recorded, except by herodotus. the cimmerians are the earliest known group from the crimean area, as recorded in contact with early semitic texts, but when the greeks showed up and started building settlements, the people they met, also iranians, were named as taurii. they did not know that the region had been inhabited by indo-european and proto-indo-european speakers for many thousands of years, but they did note the presence of a slightly different group of farmers along the dnieper (borysthenes), in addition to the ruling class of mounted warrior kings. 

you might imagine the greeks might have had some interaction with assyrian history during the period of persian hegemony. in fact, the greeks famously found the ruins of the assyrians when they entered the area behind alexander, and they did not know what culture the ruins belonged to, or what they had found. grecian curiosity of course found the answer. the assyrians were forgotten under persian hegemony, due to their cruelty. nobody wanted to remember them; everybody wanted to forget them. it took a lot of effort to remember them.

the persians left us no writing of any sort, which is bizarre. we know they could write, and appeared to prefer to write in aramaic. while there is no clear historical record of it, it seems that the arabs must have systematically burned anything related to persian writing, during the great translation event. anything the persians might have left us about assyria was lost in this process. the last persians appear in history as kurdish scholars during the pax arabica in baghdad, which was further destroyed during the mongol invasions. it is possible that some ancient persian writing was converted to arabic by kurdish or other scholars, and then burned and forgotten; there is no record of this. we simply have no surviving writing of any sort from thousands of years of persian civilizaton, and future historians will be forgiven for concluding they must have been illiterate, which is false.

this is a greek map, c -500.

you might try to build a map from scraps of stones found in assyrian ruins, but the archaeology in ukraine itself is more useful:

http://miku.org.ua/en/jewelry_art/cimmerian_scythian_and_sarmatian_arts_9th_century_bce_4th_century_ce.html

the greeks called the area the cimmerian bosporus and set up a greek client state which was half greek and half iranian. the greeks were replaced by the romans, who were driven out by iranic groups and then colonized by east germanic groups (the goths). the huns then swept into the region and killed everybody, generating waves of germans and iranians to the west, where they invaded the roman empire. it's not widely understood that there was substantive iranian migration into france during this period; the name alain is iranian in origin, and france has tons of iranian place names.

the huns were the first turkic group into the region, and their migration into it is well documented, if a little blurry. they were followed by other turkic groups like bulgars and khazars. these people are not indigenous to the region, but violently displaced the indigenous iranian people and then held on to their conquests for a few centuries.

the khazars were defeated by a confederation of swedes, who set up colonies in the region to trade with the romans, and indigenous slavs. the old legends claim that the slavs actually asked for the swedes to rule over them. i can believe that the slavs may have sought an alliance with the swedes to expel the turkish groups and, together, the two of them did. this new confederation, called rus, took control of most of modern ukraine in the 9th century, including crimea. the greeks, however, had come back and set up new trading posts. something akin to antiquity reasserted itself, with the swedes as the new royal scythians, the byzantines as the new greeks and the scythian farmers, the slavs, continuing as they always had. after the schism between catholics and orthodox, italian traders took over for byzantine traders in crimea. the populations continued to speak greek under italian control.

the mongols destroyed russia in the 13th century, and took control of the crimean peninsula in the process. this is where the crimean khanate originates from - a recent migration from east asia. however, they had a hard time maintaining control of the greek cities on the coast, who kept revolting. eventually, those cities were conquered by the ottomans, and the tatars became a client of the turks.

the scythian farmers of herodotus, the actually indigenous slavs, had since regrouped and had begun to expel mongols and turks from their homeland. they were eventually usurped by a german-speaking ruling class, a new royal scythian, and this new german-slav confederation moved south to reclaim crimea from the usurping turks a second time, this time in the 18th century. the new slavic mega state reincorporated the conquered regions - which correspond closely to the regions putin has recently reclaimed  - as new russia.

the tatars were tolerated to an extent, as conquered and absorbed turks were elsewhere in the new slavic megastate of muscovy, but it should be remember that the slavs were expelling a violent occupier. the crimean tatar economy for centuries was based on capturing and selling ukranians to turks as chattel slaves. this is where the name ukraine comes from. if the indigenous slavs wanted to enact some level of revenge on their cruel overlords, they had every justification to do so. 

slavic history is attractive to a marxist, or an engelian (?), because it has so much process. an enslaved, oppressed indigenous group (the slavs) rose up and overthrew it's cruel rulers (the turks), expelling them from their land and reducing them to tribute. eventually, stalin just shipped them back to mongolia, where they came from, and while that might have been an overreaction due to a perception that hitler tried to take advantage of them, who can blame him for it, really?

the narrative that tatars are indigenous to crimea is not merely historically wrong, it is grossly offensive. the tatars were a vicious, oppressive group of invaders that enslaved the actual indigenous people, the slavs.

this is western propaganda at it's worst.