He became the first President (1960–65) of the Democratic Republic of Congo. He was a member of undercover nationalist associations to free the Congo of the Belgians. In 1955 he became President of Abako (Alliance des Bakongo), a cultural association of the Bakongo tribe, and turned it into a powerful political organization. On independence in 1960 he became Head of State. His Abako party formed a coalition with Lumumba’s party, and then ousted him as premier. In 1965 he himself was deposed from the Presidency by Mobutu in a bloodless military coup.