The Ohlone, named Costanoan by early Spanish colonists (the Spanish word costa means "coast"), are a Native American people of the Northern California coast.

When Spanish explorers and missionaries arrive  in the late eighteenth century, the Ohlone inhabit the area along the coast from San Francisco Bay through Monterey Bay to the lower Salinas Valley.

At this time they speak a variety of related languages.

The Ohlone languages belong to the Costanoan sub-family of the Utian language family, which itself belongs to the proposed Penutian language phylum.

The term "Ohlone" has been used in place of "Costanoan" since the 1970s by some tribal groups and by most ethnographers, historians, and writers of popular literature.

In pre-colonial times, the Ohlone lived in more than fifty distinct landholding groups, and did not view themselves as a distinct group.

They lived by hunting, fishing, and gathering, in the typical ethnographic California pattern.

The members of these various bands interacted freely with one another.

The Ohlone people practice the Kuksu religion.

Prior to the Gold Rush, the northern California region is one of the most densely populated regions north of Mexico.

However, in the years 1769 to 1833, the Spanish missions in California have a negative effect on Ohlone culture, and the Ohlone population declines steeply during this period.

The Ohlone living today belong to one or another of a number of geographically distinct groups, most, but not all, in their original home territory.

The Muwekma Ohlone Tribe has members from around the San Francisco Bay Area, and is composed of descendants of the Ohlones/Costanoans from the San Jose, Santa Clara, and San Francisco missions.

The Ohlone/Costanoan Esselen Nation, consisting of descendants of intermarried Rumsen Costanoan and Esselen speakers of Mission San Carlos Borromeo, are centered at Monterey.

The Amah-Mutsun Tribe are descendants of Mutsun Costanoan speakers of Mission San Juan Bautista, inland from Monterey Bay.

Most members of another group of Rumsien language, descendants from Mission San Carlos, the Costanoan Rumsien Carmel Tribe of Pomona/Chino, now live in southern California.

These groups, and others with smaller memberships are separately petitioning the federal government for tribal recognition.