The 174th Air Defense Artillery Brigade is an Air Defense Artillery brigade of the United States Army. It is one of six brigade-sized major subordinate commands of the Ohio Army National Guard, activated on 1 September 2008, in Columbus, Ohio. Before, during, and following its activation, the brigade and its subordinate battalions have been very active, deploying individuals and units to support the Iraq War's Operation Iraqi Freedom, airspace defense of the National Capital Region, and the combined Hungary-United States Operational Mentor and Liaison Team.