The 101st Cavalry Regiment is a unit of the New York National Guard that has existed since 1921 and which saw service in World War II. The regiment was constituted on 30 December 1920 from the 1st and 2nd New York Cavalry Regiments and had its headquarters in Brooklyn. The regiment was initially assigned to the 21st Cavalry Division. The regiment was inducted into federal service in January 1941 and reorganized. The 1st Squadron was retitled the 101st Cavalry Reconnaissance Squadron (Mechanized) while the 2nd Squadron became the 116th Cavalry Reconnaissance Squadron (Mechanized). The regimental headquarters troop became the headquarters of the 101st Cavalry Group (Mechanized). With this organization, the group saw combat in northwest Europe during World War II with the XV and the XXI Corps