In the 10th century the emerging state of Kyivan Rus came increasingly under the cultural influence of the Byzantine Empire. The first recorded Rus' convert to Eastern Orthodoxy, the Princess Saint Olga, visited Constantinople in 945 or 957. In the 980s, according to tradition, Olga's grandson, Knyaz (Prince) Vladimir had his people baptised in the Dnieper River. This began a long history of the dominance of Eastern Orthodoxy in Ruthenia, a religious ascendancy that would later influence both Ukraine and Russia. Domination of Little Russia by Great Russia (from 1721) eventually led to the decline of Uniate Catholicism (officially founded in 1596) in the Ukrainian lands under Tsarist control.