The South African Army is the ground warfare branch of South African National Defence Force. Its roots can be traced to its formation after the Union of South Africa was created in 1910. The South African military evolved within the tradition of frontier warfare fought by Boer Commando (militia) forces, reinforced by the Afrikaners' historical distrust of large standing armies. It then fought as part of the wider British effort in both World War I and World War II, but afterwards was cut off from its long-standing Commonwealth ties with the ascension to power of the National Party in South Africa in 1948. The army was involved in a long and bitter counter-insurgency campaign in Namibia from 1966 to 1990. It also played a key role in controlling sectarian political violence inside South Africa during the late 1980s and early 1990s.