The 4th Cavalry Brigade traces its Lineage and Honors to the 4th Tank Destroyer Group, activated 1 September 1942 at Camp Hood, Texas and deployed to the European Theater of Operation in August 1944. The unit landed in France and saw extensive action in Europe, with campaign credits for Normandy, Northern France, Rhineland, Ardennes-Alsace, and Central Europe. The 4th Tank Destroyer Group was deactivated in 1945 and disbanded in 1952.
Headquarters, 4th Cavalry Brigade was reconstituted and activated in October 1997 at Fort Knox, Kentucky, assuming the mission of a Reserve training support Brigade. In addition to providing pre-mobilization leader and collective training assistance, the Brigade provided assistance to civilian
authorities during peacetime crises and natural disaster. In 1998, the Brigade was instrumental in the execution of the first Air Defense Artillery Lane training for the 278th Armored Cavalry Regiment of the Tennessee Army National Guard. This training resulted in the first integrated annual training at Fort Stewart, Georgia.
As part of the Training Support XXI program and the CONUS training element restructuring of the First and Fifth Armies, the unit was inactivated in
October 1999, and reactivated in December 2006 under the 85th Training Division. At this time, the unit became a Multi-Functional Training Brigade
with five subordinate battalions, responsible for the combat training of Soldiers and units from across the country. The 4th Cavalry Brigade quickly
became one of First Army's most valuable training resources, mobilizing units in seven locations across the U.S. Army North Area of Responsibility.
In January 2012, the Brigade began training Provincial Reconstruction Teams in support of several global campaigns. As part of this training, the 4th
Cavalry Brigade trainers would often accompany these teams to their deployed location for up to 60 days. Today, 4th Cavalry Observes, Coaches, Trains, Mentors, and Validates Reserve Component partners nationwide for worldwide deployment.