Until 1991, South African law divided the population into four major racial categories: blacks, whites, coloureds, and Asians. Blacks comprise about seventy-five percent of the population and are divided into a number of different ethnic groups including those from Angola and Mozambique who are descendants of refugees who have settled South Africa. Whites comprise about thirteen percent of the population. They are primarily descendants of Dutch, French, English, and German settlers who began arriving at the Cape in the late 17th century. There is a Portuguese minority including the descendants of the first European explorers and the Portuguese who left the former Portuguese colonies of southern Africa (Angola and Mozambique) after their independence in the mid-70s. Coloureds are mixed-race people primarily descended from the earliest settlers, their slaves, and the indigenous peoples. They comprise about nine percent of the total population. Most Asians descend from Indian indentured workers who came to South Africa in the mid-19th century to work on the sugar estates in Natal. Others include the descendants of Indian traders who migrated to South Africa at around the same time. They constitute about three percent of the population and are concentrated in the KwaZulu-Natal Province. There is also a small Chinese population of approximately 100,000 people.