There are three basic racial sources for the Brazilian people. To the original inhabitants (Indians) were added successive waves of Europeans (mainly Portuguese) and Africans (mostly from the sub-Saharan west coast).

In the 16th century, the area which is now Brazil was inhabited by several hundred Indigenous tribes who, while racially similar, spoke different languages and had different cultures. Groups speaking the Tupi and Guarani languages lived along the coast and in the adjoining hinterland and they established intermarriages with the Portuguese settlers. Many tribes speaking other languages (Gê, Arwak, and Karib), on the other hand, lived in the interior and they took longer to establish contact with the outsiders. Today Brazil's native Indians number about 250,000. They are divided into roughly 200 groups and they speak some 180 different languages. The Indians live in vast areas (328,185 sq. miles [850,000 sq. km]), equal to ten percent of Brazil's total territory, which has been set aside from them by the Federal Government. In these areas, which total more than twice the size of the state of California, the Indians are free to preserve their life-style.

Starting in the middle of the 16th century, Africans belonging to the Bantu and to the Sudanic ethnic groups (a large proportion of the Sudanic group came from the Yoruba nation from what is today Nigeria and Benin) were brought to Brazil to work as slaves in the sugarcane, and later, in the gold and diamond mines and the coffee plantations. The integration process that had begun between the Europeans and the Indians rapidly spread to include the black slaves.

This racial mixing went on as Brazil began, at the end of the 19th century, to receive increasing numbers of immigrants from all over the world. Portugal remained the single most important source of migrants to Brazil, with Italy second, followed by Lebanon. In the first half of the 20th Century, as a consequence of war or economic pressures, sizable contingents of immigrants came to Brazil from parts of western, central, and eastern Europe. In 1908, 640 immigrants came to Brazil from Japan. Because of the welcoming social environment, a Japanese migration trend was established. By 1969, 247,312 Japanese had emigrated to Brazil. Today Brazilians of Japanese descent are the largest such group outside Japan.