The 115th Infantry Regiment, Maryland Army National Guard was an infantry regiment of the United States Army. It traced its roots back to the American Revolutionary War, although its official U.S. Army lineage begins in 1881. The units to which the 115th Regiment claims lineage served in the Revolutionary War and the Civil War, but the 115th itself was only credited with service in World War I, World War II, and the Global War on Terror. Prior to the reorganization into the 58th Brigade Combat Team, the 1–115th was part of the Third Brigade, 29th Infantry Division (Light). In 2006, the 115th was consolidated (merged) with the 175th Infantry Regiment. As a result of this consolidation, it no longer exists as a separate regiment.

The Maryland Army National Guard is the United States Army component of the U.S. state of Maryland. It is headquartered at the old Fifth Regiment Armory at the intersection of North Howard Street, 29th Division Street, near Martin Luther King, Jr. Boulevard in Baltimore and has additional units assigned and quartered at several regional armories, bases/camps and other facilities across the state.