The Union began an offensive across Arkansas in early 1862 in which General Samuel Curtis led troops near Leetown, where the Battle of Pea Ridge occurred. After securing a Union victory, Curtis swept across the state to Helena. Curtis intended to knock Arkansas out of the war by capturing Little Rock. However, reinforcements arrived in Spring 1862 under General William Steele. General Thomas C. Hindman, although recently defeated at the Battle of Cotton Plant, attempted to return northwest Arkansas to Confederate control. The Battle of Prairie Grove was essentially a stalemate, but Hindman's unit withdrew to Van Buren and was driven from the region completely by December 1862. Union troops defeated a Confederate attack in the Battle of Fayetteville on April 18, 1863, but a week later abandoned Northwest Arkansas and retreated to Missouri for the summer.