Before European contact, the temperate California area had more people than any other North American landscape at the time, with approximately 300,000 people in the mid-16th century. It's estimated that 100 different tribes and groups spoke more than 200 dialects. These languages were derived from the Penutian (the Maidu, Miwok and Yokuts), the Hokan (the Chumash, Pomo, Salinas and Shasta), the Uto-Aztecan (the Tubabulabal, Serrano and Kinatemuk) and the Athapaskan (the Hupa, among others). Many of the “Mission Indians” who were driven out of the Southwest by Spanish colonization also spoke Uto-Aztecan dialects.
Despite this great diversity, many native Californians lived very similar lives. They did not practice much agriculture. Instead, they organized themselves into small, family-based bands of hunter-gatherers known as tribelets. Inter-tribelet relationships, based on well-established systems of trade and common rights, were generally peaceful.
Spanish explorers infiltrated the California region in the middle of the 16th century. In 1769, the cleric Junipero Serra established a mission at San Diego, inaugurating a particularly brutal period in which forced labor, disease and assimilation nearly exterminated the culture area’s native population.