409th may refer to: __NOTOC__ Soviet Union 409th Rifle Division, 1941–1945
United Kingdom 409th Coast Regiment, Royal Artillery or 1st Cornwall (Duke of Cornwall's) Artillery Volunteers 409th (Suffolk) Heavy Anti-Aircraft Battery, Royal Artillery or 1st Suffolk Artillery Volunteer Corps
United States 409th Air Expeditionary Operations Group, provisional United States Air Force unit assigned to Air Mobility Command 409th Bombardment Squadron or 909th Air Refueling Squadron (909 ARS), part of the 18th Wing at Kadena Air Base, Japan 409th Fighter Squadron or 194th Fighter Squadron, aviation unit of the California Air National Guard 409th Support Brigade (United States), support brigade of the United States Army 409th Bomb Squadron, 93rd Bomb Group, 8th Air Force, United States Army Air Force, B-24 Liberators, Flying Pandas, Hardwick, England, World War II European Theater
See also 409 (number) 409, the year 409 (CDIX) of the Julian calendar 409 BC