From this process of cultural contact and state formation, three different types of states emerged. The Tutsi type was later to be seen in Rwanda and Burundi. It preserved a caste system whereby the rulers and their pastoral relatives attempted to maintain strict separation from the agricultural subjects, called Hutu. The Tutsi rulers lost their Nilotic language and became Bantu speakers, but they preserved an ideology of superiority in political and social life and attempted to monopolise high status and wealth. In the 20th century, the Hutu revolt after independence led to the expulsion from Rwanda of the Tutsi elite, who became refugees in Uganda. A counter-revolution in Burundi secured power for the Tutsi through periodic massacres of the Hutu majority.