21st Regiment

21st Regiment may refer to:

Infantry regiments

• 21 Regiment Special Air Service, a unit of the British Army
• 21st Foot, a former regiment of the British Army
• 21st Infantry Regiment (Thailand), a unit of the Royal Thai Army
• 21st Infantry Regiment (United States), a unit of the United States Army
• 21st Punjabis, a unit of the British Indian Army
• 21st Marine Infantry Regiment, a unit of the French Marines
• 21st Marine Regiment (United States), a unit of the United States Marine Corps

American Revolutionary War regiments

• 21st Continental Regiment

American Civil War regiments

• 21st Iowa Volunteer Infantry Regiment
• 21st Illinois Volunteer Infantry Regiment
• 21st Maine Volunteer Infantry Regiment
• 21st Michigan Volunteer Infantry Regiment
• 21st Mississippi Infantry Regiment
• 21st Ohio Infantry
• 21st Kansas Militia Infantry Regiment
• 21st Regiment Kentucky Volunteer Infantry
• 21st Regiment Massachusetts Volunteer Infantry
• 21st Wisconsin Volunteer Infantry Regiment

Cavalry regiments

• 21st Lancers, a unit of the British Army

Engineer regiments

• 21st Construction Regiment (Australia), a former unit of the Australian Army's Engineers
• 21 Engineer Regiment (United Kingdom), a unit of the British Army's Royal Engineers

See also

• XXI Corps (disambiguation)
• 21st Brigade (disambiguation)
• 21st Division (disambiguation)
• 21 Squadron (disambiguation)
• Regiment