Fossils and cave paintings in Kenya and northern Tanzania suggest that the white rhino was widespread in East Africa until 3,000 years ago.
While Kenya has not been a white rhino range state in the last two hundred years, evidence from fossils and cave paintings in Kenya and northern Tanzania suggest that the white rhino, presumably similar to the northern race (Ceratotherium sinum cottoni,) was widespread and a part of the East African savanna fauna until 3,000 years ago or less when it was probably displaced by pastoralists who could easily kill such tame animals. This is based on the white rhino sub-fossil documented by Maeve Leakey from 3,000 year from the Lake Nakuru area of Rift Valley.
Thus, at one stage, Kenya was once a white rhino range state (subspecies unknown,) and hence the white rhino as a species, but not C. s. simum as a subspecies, has probably been reintroduced to Kenya (with the latter being an introduction of a probable out of range subspecies.) A recent report of a white rhino hunting trophy from Kenya in an Austrian Museum still has to be confirmed but merits further investigation.