An 1831 graduate of West Point, Samuel Curtis left the army after a year and eventually entered the law and politics. At the outbreak of the Civil War, he resigned his Iowa congressional seat (1856-61) to become colonel of the 2nd Iowa Volunteer Infantry.
Rising rapidly to commander of the Army of the Southwest, he defeated a Confederate army led by Major General Earl Van Dorn at the Battle of Pea Ridge, Arkansas, in March 1862. After a difficult 1,000-mile march in July and August, Curtis captured Helena, Arkansas, securing yet another victory for the Union. In September he was appointed commander of the Department of the Missouri. Curtis also served as commander of the Departments of Kansas and the Northwest.
In 1864 troops under Curtis's command checked Sterling Price's Missouri Raid of 1864, a battle that cost Price thousands of small arms, and all his cannon, and most of his men. After the war, Curtis was appointed an Indian commissioner.