1st Cavalry, 1st Cavalry Division, 1st Cavalry Brigade, 1st Cavalry Regiment or 1st Cavalry Battalion may refer to:
Armies 1st Cavalry Army, Soviet Union
Corps I Cavalry Corps (Grande Armée) I Cavalry Corps (German Empire) I Cavalry Corps (Wehrmacht) 1st Cavalry Corps (Russian Empire) 1st Guards Cavalry Corps
Divisions 1st Cavalry Division (Australia) 1st Cavalry Division (Belgium) 1st Light Cavalry Division (France) 1st Foot Cavalry Division (France) 1st Cavalry Division (German Empire) 1st Cavalry Division (Reichswehr), Germany 1st Cavalry Division (Wehrmacht), Germany 1st Cossack Cavalry Division, a unit of the Wehrmacht, Germany 1st Indian Cavalry Division 1st Cavalry Division Eugenio di Savoia, a unit of the Royal Italian Army 1st Cavalry Division (Poland) 1st Cavalry Division (Russian Empire) 1st Guards Cavalry Division (Russian Empire) 1st Cavalry Division (Soviet Union) 1st Mountain Cavalry Division (Soviet Union) 1st Cavalry Division (United Kingdom) 1st Cavalry Division (United States) 1st Cavalry Division (Kingdom of Yugoslavia)
Brigades 1st Cavalry Brigade (Australia) 1st Mechanized Cavalry Brigade, Brazil 1st Cavalry Brigade (France) 1st Cavalry Brigade (Wehrmacht), Germany 1st Cavalry Brigade (Hungary) 1st (Risalpur) Cavalry Brigade, a unit of the Indian Army 1st Cavalry Brigade (Imperial Japanese Army) 1st Cavalry Brigade (Poland) 1st Cavalry Brigade (United Kingdom) 1st Cavalry Brigade (United States) 1st Air Cavalry Brigade, 1st Cavalry Division (United States)
Regiments and battalions
France 1st Foreign Cavalry Regiment, a unit of the French Foreign Legion 1st Polish Light Cavalry Regiment of the Imperial Guard, a unit of Napoleonic France 1st Spahi Regiment 1st Parachute Hussar Regiment
Germany 1st Royal Bavarian Heavy Cavalry (Prince Charles of Bavaria's) 1st Royal Bavarian Chevau-légers "Emperor Nicholas of Russia" 1st Royal Bavarian Uhlans "Emperor William II, King of Prussia" 1st Royal Saxon Guards Heavy Cavalry 1st King's Mounted Rifles 1st (Silesian) Life Cuirassiers "Great Elector" 1st Guards Uhlans
United States 1st Cavalry Regiment (United States) 1st Cavalry Regiment (1855) 1st United States Volunteer Cavalry
Union Army (American Civil War) 1st Regiment Alabama Cavalry (Union) 1st Regiment Arkansas Cavalry (Union) 1st California Cavalry Regiment 1st California Cavalry Battalion 1st Colorado Cavalry Regiment 1st Connecticut Cavalry Regiment 1st Dakota Cavalry Battalion 1st Florida Cavalry Regiment (Union) 1st Illinois Cavalry Regiment 1st Iowa Volunteer Cavalry Regiment 1st Louisiana Cavalry Regiment (Union) 1st Maine Volunteer Cavalry Regiment 1st Regiment Maryland Volunteer Cavalry 1st Maryland Cavalry Regiment 1st Michigan Volunteer Cavalry Regiment 1st Minnesota Volunteer Cavalry Regiment 1st Regiment Nebraska Volunteer Cavalry 1st New Jersey Volunteer Cavalry 1st Ohio Cavalry 1st Oregon Volunteer Cavalry Regiment 1st Pennsylvania Cavalry Regiment 1st Rhode Island Cavalry 1st Texas Cavalry Regiment (Union) 1st United States Colored Cavalry Regiment 1st Vermont Cavalry 1st West Virginia Volunteer Cavalry Regiment 1st Wisconsin Volunteer Cavalry Regiment
Confederate Army (American Civil War) 1st Regiment Alabama Volunteer Cavalry (Confederate) 1st Arkansas Cavalry Regiment (Crawford's) 1st Arkansas Cavalry Regiment (Dobbin's) 1st Cavalry Regiment, Arkansas State Troops 1st Florida Cavalry Regiment (Confederate) 1st Florida Special Cavalry Battalion 1st Georgia Cavalry 1st Battalion, Georgia Cavalry 1st Louisiana Cavalry Regiment (Confederate) 1st Mississippi Cavalry Regiment 1st North Carolina Cavalry Regiment 6th Arkansas Cavalry Regiment, also known as the 1st Trans-Mississippi Cavalry Regiment 1st Virginia Cavalry
Others 1st Cavalry Regiment (Chile)