At the end of the Ice Age, the ancestors of the California Indians left Asia, came across the Bering Straits into North America. and filtered southward into California, where they settled along the coast and in river valleys.
Nearly all of California's first inhabitants were hunters and gatherers of food rather than agriculturists or herdsmen. Most of them ate little meat but subsisted on a diet of grasses, herbs, roots, berries, and nuts, in addition to seafood where it was available. The live oak trees of central and southern California provided an abundant supply of acorns, which the Indians of that extensive subcultural area ground into flour for baking into bread or for boiling to make a thick soup. The coastal Indians obtained an ample supply of fish and other seafood from the Pacific Ocean and its bays and estuaries, and the northern tribes built an economy around river salmon. Only the Yuman
Indians along the Colorado River in southern California grew corn.
The topography and climate of California, with its pervasive mountain ranges and its lack of navigable rivers, encouraged isolation and diversification among the Indian groups, who were extremely different physically as
well as culturally. The California Indians comprised some of the tallest and some of the shortest Indians on the continent, and their skeletal forms, facial characteristics. and skin types were widely dissimilar. They spoke 13
different idioms from 21 or 22 linguistic subdivisions of 7 basic language groups.
The California Indians were neither warlike nor nomadic, and they had little in the way of a system of government. Their religious life was centered around their relationship to nature, and they had a remarkable ability to adjust to the demands of their particular habitats. They had few weapons. and used nets or traps to catch fish and game. They excelled in basket weaving. which they developed into a fine art, and except for the
Yumans, made no pottery.
Many California Indian dwellings were constructed from poles set into the ground and lashed together at the top; this conical-shaped framework was then either banked with earth or covered with thatch material of various
types. A few tribes made semi-underground dwellings, the upper portions of which were covered with earth. In the northwest, houses with gabled roofs were built with lumber from the redwood and fir trees.
The arrival of the Spanish in California heralded the beginning of a decline in the Indian population. Great numbers died from European diseases (to which they had no natural immunity) and as a result of neglect and mistreatment by subsequent migrants to California. By 1880 the Indian population had been
reduced to 20,000 from the 133.000 to 275,000 who were living throughout the state when the Spanish period began.