First, 1st Battalion, 1st Marines, 1st Cavalry, 1st Reconnaissance Battalion, 1st Operations Group, 1st Regiment, 1st Senate district, 1st Mounted Division, 1st Fighter Brigade, 3rd Battalion, 1st Marines, Royal 1st Devon Yeomanry, 1st Division, 1st Rifle Division, 1st Armoured Infantry Brigade (United Kingdom), 1st Brigade Combat Team, 1st Cavalry Division (United States), 1st Word, 1st Pennsylvania Regiment, 1st Squadron, 1st Cavalry Regiment, 1st Marine Expeditionary Brigade (United States), 1st Theater Sustainment Command, 1st Hussars, 1st Reconnaissance Squadron, 2nd Battalion, 1st Marines, 1st Brigade, 1st Armored Division (United States), 1st Marine Regiment (United States), 1st Brigade Combat Team, 1st Infantry Division (United States), 1st Michigan Infantry Regiment, 1st & Ten, 1st Marine Division, 1st Distribution Support Battalion, 1st Arkansas Infantry Regiment, 1st Maryland Cavalry Battalion, 1945–46 Danish 1st Division, 1st Brigade Combat Team, 1st Arkansas Cavalry Regiment, 1st Kentucky Infantry Regiment, 1955–56 Danish 1st Division, 1951–52 Danish 1st Division, 1947–48 Danish 1st Division, 1946–47 Danish 1st Division

1st Artillery Regiment, 1949–50 Danish 1st Division, 1948–49 Danish 1st Division, 1st Kentucky Cavalry Regiment, 1952–53 Danish 1st Division, 1950–51 Danish 1st Division, 1st Airborne, 1st Missouri Infantry Regiment, 1st Engineer Regiment (Italy), 1st (UK) Division, 1953–54 Danish 1st Division, 1st Louisiana Infantry Regiment, 1954–55 Danish 1st Division, 1st Bombardment Wing, 1st Constitution Bancorp, 1st Air Defense Artillery Regiment, 1st Maryland Infantry Regiment, 1st Delaware Infantry Regiment, 1st Brigade (Australia), 1st Louisiana Cavalry Regiment, 1st Airborne Command Control Squadron, 1st Armoured Brigade (United Kingdom), 1st Belorussian Front, 1st Division (Thailand), 1st Battle Squadron, 1st Colorado Infantry Regiment, 1st ward, Chicago, 1st Combat Engineer Battalion, 1st Division (Australia), 1st Horse (Skinner's Horse), 1st Cavalry Division (United States), 1st Armored, 1st Infantry Division (United States), 1st (African) Division, 1st Infantry Regiment (United States), 1st Canadian Parliament, 1st Parachute Division (Germany), Ōita 1st district, 1st Medical Brigade, 1st Expeditionary Rescue Group, 1st Georgia Infantry Regiment, Francis Cook, 1st Viscount of Monserrate, 1st Anti-Aircraft Brigade, 1st Royal New South Wales Lancers, 1956–57 Danish 1st Division, 1st Light Car Patrol (Australia), 1st Armored Division (France), 1st Infantry Division (France), 1st Test and Evaluation Squadron, 1st Fighter Wing

First, 1st Battalion, 1st Marines, 1st Cavalry, 1st Reconnaissance Battalion, 1st Operations Group, 1st Regiment, 1st Senate district, 1st Mounted Division, 1st Fighter Brigade, 3rd Battalion, 1st Marines, Royal 1st Devon Yeomanry, 1st Division, 1st Rifle Division, 1st Armoured Infantry Brigade (United Kingdom), 1st Brigade Combat Team, 1st Cavalry Division (United States), 1st Word, 1st Pennsylvania Regiment, 1st Squadron, 1st Cavalry Regiment, 1st Marine Expeditionary Brigade (United States), 1st Theater Sustainment Command, 1st Hussars, 1st Reconnaissance Squadron, 2nd Battalion, 1st Marines, 1st Brigade, 1st Armored Division (United States), 1st Marine Regiment (United States), 1st Brigade Combat Team, 1st Infantry Division (United States), 1st Michigan Infantry Regiment, 1st & Ten, 1st Marine Division, 1st Distribution Support Battalion, 1st Arkansas Infantry Regiment, 1st Maryland Cavalry Battalion, 1945–46 Danish 1st Division, 1st Brigade Combat Team, 1st Arkansas Cavalry Regiment, 1st Kentucky Infantry Regiment, 1955–56 Danish 1st Division, 1951–52 Danish 1st Division, 1947–48 Danish 1st Division, 1946–47 Danish 1st Division, 1st Artillery Regiment, 1949–50 Danish 1st Division, 1948–49 Danish 1st Division, 1st Kentucky Cavalry Regiment, 1952–53 Danish 1st Division, 1950–51 Danish 1st Division, 1st Airborne, 1st Missouri Infantry Regiment, 1st Engineer Regiment (Italy), 1st (UK) Division, 1953–54 Danish 1st Division, 1st Louisiana Infantry Regiment, 1954–55 Danish 1st Division, 1st Bombardment Wing, 1st Constitution Bancorp, 1st Air Defense Artillery Regiment, 1st Maryland Infantry Regiment, 1st Delaware Infantry Regiment, 1st Brigade (Australia), 1st Louisiana Cavalry Regiment, 1st Airborne Command Control Squadron, 1st Armoured Brigade (United Kingdom), 1st Belorussian Front, 1st Division (Thailand), 1st Battle Squadron, 1st Colorado Infantry Regiment, 1st ward, Chicago, 1st Combat Engineer Battalion, 1st Division (Australia), 1st Horse (Skinner's Horse), 1st Cavalry Division (United States), 1st Armored, 1st Infantry Division (United States), 1st (African) Division, 1st Infantry Regiment (United States), 1st Canadian Parliament, 1st Parachute Division (Germany), Ōita 1st district, 1st Medical Brigade, 1st Expeditionary Rescue Group, 1st Georgia Infantry Regiment, Francis Cook, 1st Viscount of Monserrate, 1st Anti-Aircraft Brigade, 1st Royal New South Wales Lancers, 1956–57 Danish 1st Division, 1st Light Car Patrol (Australia), 1st Armored Division (France), 1st Infantry Division (France), 1st Test and Evaluation Squadron, 1st Fighter Wing, 1st Arkansas Consolidated Infantry Regiment, 1st Brahmans, 1st Fighter Squadron, 1st Low Altitude Air Defense Battalion, 1st Source, 1st Pontieri Regiment, 1st Cavalry Regiment (United States), 1st (Peshawar) Division, 1st Foreign Regiment (France), 1st Special Operations Squadron, 1st Earl of Suffolk, Joseph Maclay, 1st Baron Maclay, 1st Civil Affairs Group, 1st Air Cavalry Brigade, 1959 Danish 1st Division, 1st Mobile Corps, 1st Wisconsin Infantry Regiment, 1st Airlanding Brigade (United Kingdom), 1st Marine Logistics Group, 1st Provisional Marine Brigade, 1st Battalion, 5th Marines, 1st Earl Temple, 1960 Danish 1st Division, 2002–03 Danish 1st Division, 2003–04 Danish 1st Division, Captain 1st rank, 1958 Danish 1st Division, 1st Force Reconnaissance Company, 1st Health Battalion (Australia), 1st Canadian Division, 1997–98 Danish 1st Division, 1996–97 Danish 1st Division, Komandarm 1st rank, 1st Ski Division (Wehrmacht), 1st Guards Brigade (Croatia), 1st GAM: Amai Yuwaku, 1st Minnesota Infantry Regiment, 1st Armoured Division (Australia), 1st Florida Cavalry Regiment, 2000–01 Danish 1st Division, 1st Marine Aircraft Wing, 1st millennium BC, 1st Armored Brigade (People's Republic of China), 1st Time, 1st Tank Brigade (Ukraine), 1st Army Corps, 1st Strategic Aerospace Division, 1st Aviation Regiment (United States), 1st Commonwealth Division, 1st Airlift Squadron, 1995–96 Danish 1st Division, 1st Brigade (New Zealand), 2001–02 Danish 1st Division, 1st Tactical Missile Squadron, 1999–2000 Danish 1st Division, 1st Alabama Cavalry Regiment, 1st Regiment, Royal Australian Artillery, 1st Viscount Hampden, 1998–99 Danish 1st Division, 1st Panzergrenadier Brigade (Germany)