He was the grandson of tribal king Khama III, and was proclaimed king himself in 1925. He attended Fort Hare University College in South Africa, and trained as a barrister at Inner Temple in London. He married an English woman, Ruth Williams.
He was exiled from Bechuanaland in 1951, and then allowed back in 1956, as a private citizen. In 1961 he founded the Bechuanaland Democratic Party, which won elections in 1965, and he himself won presidential elections in 1966. He remained president until his death in 1980.