Between the conclusion of the Anglo-Boer War and the unification of South Africa, the mines suffered from a shortage of unskilled labour . Most Africans still lived by agriculture, either as tenant farmers on white farms or in reserves created by the colonial government. They had no need to desert their traditional farming way of life for a thankless existence in shantytowns far away from home. To counter this, the government took measures to compel them to supply their labour. One method was the imposition of taxes that had to be paid in coin, thus forcing Africans from subsistence farming and into the cash economy, where they would have to earn a wage. Responding to one such tax, a group of Zulus protested in 1906 and refused to pay up. The authorities declared martial law and dealt mercilessly with the protesters, burning their huts and seizing all their possessions. This provoked a full-blown rebellion led by Chief Bambatha, which was ruthlessly put down by the colonial authorities, with 4000 rebels dying in the process. This marked an end to armed resistance by Africans for over half a century. After the defeat of the Bambatha Rebellion , the numbers of African men from Zululand working in the Gauteng mines shot up by sixty percent. By 1909, eighty percent of adult males in the territory were absent from their homes and working as migrant labourers. Migrant labour , with its shattering effects on family life, became one of the foundations of South Africa's economic and social system, and was a basic cornerstone of apartheid.