Thomas Armstrong Morris was an American railroad executive and civil engineer from Kentucky and a soldier, serving as a brigadier general of the Indiana Militia in service to the Union during the early months of the American Civil War. During the Western Virginia Campaign in 1861, he played an important role in leading regiments from West Virginia, Indiana, and Ohio in clearing the Confederate army from western Virginia during the Battle of Philippi, a move that helped bolster pro-Union sentiment and contributed to the creation of the separate state of West Virginia. Morris was also instrumental in the planning and construction of the Reconstruction era Indiana State House.

The western Virginia campaign, also known as operations in western Virginia or the Rich Mountain campaign, occurred from May to December 1861 during the American Civil War. Union forces under Major General George B. McClellan invaded the western portion of Virginia to prevent Confederate occupation; this area later became the state of West Virginia. West Virginians on both sides would fight in the campaign while a Unionist convention in Wheeling would appoint their choice for a Unionist governor for Virginia, Francis H. Pierpont, and promote the creation of a new state in western Virginia. Large scale Confederate forces would gradually abandon the region, leaving it to small local brigades to maintain hold on southern and eastern sections for much of the war.