The 503rd Infantry Regiment and the 2nd Infantry Division are both formations of what military branch
503rd Infantry Regiment (United States) The 503rd Infantry Regiment, formerly the 503rd Parachute Infantry Regiment (PIR) and the 503rd Airborne Infantry Regiment (AIR), is an airborne infantry regiment of the United States Army. The regiment served as an independent regiment in the Pacific War during World War II; at Fort Campbell, Kentucky; in Okinawa, Japan; and in Germany. Regimental elements have been assigned to the 2nd Infantry Division, the 11th Airborne Division, the 24th Infantry Division, the 82nd Airborne Division, and the 173rd Airborne Brigade Combat Team. Regimental elements have participated in campaigns in the Vietnam War, Operation Enduring Freedom–Afghanistan, and Operation Iraqi Freedom. The regiment claims 15 Medal of Honor recipients: two from World War II, 10 from Vietnam, and three from Afghanistan. A parent regiment under the U.S. Army Regimental System. The regiment's 1st and 2nd Battalions are active, assigned to the 173rd Airborne Brigade, based at Caserma Ederle, Vicenza, Italy.
Functional brigade A functional brigade —or functional support brigade— is a brigade specialized in combat support or combat service support for a particular military role. The primary purpose of a functional brigade is to plug into operational formations at the theater level or those commanded by corps or division commanders performing as the Army Service Component Command (ASCC) once deployed, and to conduct operational or theater level tasks or support. Functional brigades, like modular support brigades, have a modular subordinate structure that may vary considerably among brigades of the same type. Unlike the modular support brigades, functional brigades typically operate under theater control and depend on theater-level elements for signal and other support. The theater force may task-organize them to corps or division headquarters. Types of functional brigades include: