The British colonial rulers introduced a system of pass laws in the Cape Colony and Natal during the 19th century. This stemmed from the regulation of blacks' movement from the tribal regions to those occupied by whites and coloureds, ruled by the British. Laws were passed not only to restrict the movement of blacks into these areas, but also to prohibit their movement from one district to another without a signed pass. Blacks were not allowed onto the streets of towns in the Cape Colony and Natal after dark and had to carry their passes at all times.
The Franchise and Ballot Act of 1892 instituted limits based on financial means and education to the black franchise, and the Natal Legislative Assembly Bill of 1894 deprived Indians of the right to vote. In 1905 the General Pass Regulations Bill denied blacks the vote altogether, limited them to fixed areas and inaugurated the infamous Pass System. Then followed the Asiatic Registration Act (1906) requiring all Indians to register and carry passes, the South Africa Act (1910) that enfranchised whites, giving them complete political control over all other race groups, the Native Land Act (1913) which prevented all blacks, except those in the Cape, from buying land outside "reserves", the Natives in Urban Areas Bill (1918) designed to force blacks into "locations", the Urban Areas Act (1923) which introduced residential segregation and provided cheap labour for white industry, the Colour Bar Act (1926), preventing blacks from practising skilled trades, the Native Administration Act (1927) that made the British Crown, rather than paramount chiefs, the supreme head over all African affairs, the Native Land and Trust Act (1936) that complemented the 1913 Native Land Act and, in the same year, the Representation of Natives Act, which removed blacks from the Cape voters' roll. The final piece of segregating legislation enacted by the British was the Asiatic Land Tenure Bill (1946), which banned any further land sales to Indians.
Jan Smuts' United Party government began to move away from the rigid enforcement of segregationist laws during World War II. Amid fears integration would eventually lead the nation to racial assimilation, the legislature established the Sauer Commission to investigate the effects of the United Party's policies. The commission concluded integration would bring about a "loss of personality" for all racial groups.