The land grants made in California were private rancho grants. The California missions held much of the best land in trust for the Indians. When the missions were secularized in 1833, many Indians chose to leave the missions when the land was divided. While Indians were allotted some land, most of the land was acquired by non-Indians. Between 1835 and 1845, nearly seven hundred land grants were made to claimants. These grants were often made to close friend or supporters of the Mexican governors of Alta California. Many claimants lost their grants when they could not prove legal ownership with the land grant commission set up after the U.S. won California as part of the Mexican American war.