Oliver Hazard Perry Throck Morton (August 4, 1823–November 1, 1877) was a U.S. Republican Party politician from Indiana. He served as Governor of Indiana in the American Civil War, and was a stalwart ally of President Abraham Lincoln. During the war, Morton suppressed the Democrat-controlled Indiana General Assembly. He exceeded his constitutional authority by calling out the militia without approval, and during the period of legislative suppression he privately financed the state government through unapproved federal and private loans. He was criticized for arresting and detaining political enemies and suspected southern sympathizers, but is remembered as one of Indiana's most successful governors who led the state during its most challenging period.