Ceran St. Vrain

Ceran St. Vrain, born Ceran de Hault de Lassus de Saint-Vrain (May 5, 1802 – October 28, 1870), was a French-American fur trader active in the American West during the 19th century. His father was a French aristocrat who emigrated to Spanish Louisiana in the late 18th century, and his mother was from St. Louis, where he was born. To gain license to trade in the frontier territories of New Spain, in 1831 he became a naturalized Mexican citizen in what is now the state of New Mexico. He formed a partnership with American traders William, George and Charles Bent, and together they established the trading post of Bent's Fort in what is now the state of Colorado. It was the only privately held fort in the West.

In addition to his trading post business, St. Vrain formed a business partnership with Cornelio Vigil. In 1843 the two men petitioned for and received a land grant of approximately 4 million acres (1,600,000 ha) located in what is now southeastern Colorado. However, their plans for development of the area were halted due to the onset of the Mexican–American War, in which the United States invaded and acquired the Southwest and California.

Following the creation of the U.S. provisional government of New Mexico in 1847, St. Vrain organized a group of volunteers who fought alongside the U.S. Army during the Taos Revolt. After the deaths of Charles and George Bent, William Bent and St. Vrain dissolved their partnership. St. Vrain settled in Mora, New Mexico Territory. There he owned saw and flourmills and was a supplier to the U.S. Army garrison at nearby Fort Union.