Prehistoric Ukraine, as part of the Pontic steppe, played an important role in Eurasian cultural contacts, including the spread of the Chalcolithic, the Bronze Age, Indo-European expansion and the domestication of the horse. Wikipedia
Part of Scythia in antiquity and settled by Getae, in the migration period, Ukraine is also the site of early Slavic expansion, and enters history proper with the establishment of the medieval state of Kievan Rus’, which emerged as a powerful nation in the Middle Ages but disintegrated in the 12th century.
On a side-note:
For Rh negative frequencies within the Ukraine, continue here: