Montgomery County is a county in the State of Alabama. As of the 2010 census, its population was 229,363, making it the fourth-most populous county in Alabama. Its county seat is Montgomery, the state capital. Montgomery County is included in the Montgomery, AL Metropolitan Statistical Area. Montgomery County was established by dividing Monroe County on December 6, 1816, by the Mississippi Territorial Legislature. It is named for Lemuel P. Montgomery, a young U.S. Army officer killed at the Battle of Horseshoe Bend, the final battle of the Creek Indian war, which was waged concurrently with the War of 1812.