The Sangre de Cristo Land Grant in the San Luis Valley of southern Colorado and northern New Mexico consists of 1,000,000 acres (4,000 km2) of mostly arid land. It was awarded by the government of New Mexico to the Beaubien family in 1843. The land grant was originally settled by Hispanics from New Mexico. Since the incorporation of the area of the grant into the United States in 1848, legal disputes between the descendants of the Hispanic settlers and Anglo ranchers about ownership of and access to some of the land in the grant area have been frequent and continued into the 21st century.

The San Luis Valley is a region in south-central Colorado with a small portion overlapping into New Mexico. The valley is approximately 122 miles (196 km) long and 74 miles (119 km) wide, extending from the Continental Divide on the northwest rim into New Mexico on the south. It contains 6 counties and portions of 3 others. It is an extensive high-elevation depositional basin of approximately 8,000 square miles (21,000 km2) with an average elevation of 7,664 feet (2,336 m) above sea level. The valley is a section of the Rio Grande Rift and is drained to the south by the Rio Grande, which rises in the San Juan Mountains to the west of the valley and flows south into New Mexico. The San Luis Valley has a cold desert climate but has substantial water resources from the Rio Grande and groundwater.