First 1st Battalion, 1st Marines 1st Cavalry 1st Reconnaissance Battalion 1st Operations Group 1st Mounted Division 1st Fighter Brigade 1st Regiment 1st Senate district 1st Division Royal 1st Devon Yeomanry 3rd Battalion, 1st Marines 1st Rifle Division 1st Armoured Infantry Brigade (United Kingdom) 1st Brigade Combat Team, 1st Cavalry Division (United States) 1st Word 1st Pennsylvania Regiment 1st Hussars 1st Theater Sustainment Command 1st Reconnaissance Squadron 1st Squadron, 1st Cavalry Regiment 2nd Battalion, 1st Marines 1st Brigade 1st Battalion, 4th Marines 1st Brigade Combat Team, 1st Infantry Division (United States) 1st Armored Division (United States) 1st Marine Regime…

ent (United States) 1st & Ten 1st Michigan Infantry Regiment 1st Brigade Combat Team 1st Distribution Support Battalion 1945–46 Danish 1st Division 1951–52 Danish 1st Division 1946–47 Danish 1st Division 1st Airborne 1st Artillery Regiment 1955–56 Danish 1st Division 1949–50 Danish 1st Division 1948–49 Danish 1st Division 1952–53 Danish 1st Division 1947–48 Danish 1st Division 1st Marine Division 1st Bombardment Wing 1950–51 Danish 1st Division 1954–55 Danish 1st Division 1st Air Defense Artillery Regiment 1st Constitution Bancorp 1953–54 Danish 1st Division 1st Minnesota Infantry Regiment 1st Missour

i Infantry 1st Brigade (Australia) 1st Delaware Infantry Regiment 1st Belorussian Front 1st Division (Thailand) 1st Armoured Brigade (United Kingdom) 1st Battle Squadron 1st Airborne Command Control Squadron 1st Armored 1st Infantry Division (United States) 1st Division (Australia) 1st Light Antiaircraft Missile Battalion 1st Combat Engineer Battalion 1st (African) Division 1st Colorado Infantry Regiment 1st Horse (Skinner's Horse) 1st Canadian Parliament 1st Expeditionary Rescue Group 1st Infantry Regiment (United States) Francis Cook, 1st Viscount of Monserrate Ōita 1st district 1st Georgia Infantry Regiment 1956–57 Danish 1st Division 1st millennium BC 1st Light Car Patrol (Australi