("Rough Riders") was originally constituted as the 5th Sanitary Trains on 10 November 1917 at Camp Logan, Texas.

During World War II, the Battalion fought on the beaches of Normandy and Northern France, through the Rhineland, into Ardenne-Alsace and Central Europe.

The 4th Medical Battalion was inactivated following the end of the Second World War on 21 February 1946, at Camp Butner, North Carolina .

On 1 May 1987, the unit was converted and re-designated as the 204th Forward Support Battalion and activated at Fort Carson, Colorado, as an element of the 4th Infantry Division.

As of 1 January 2006, the 204th Brigade Support Battalion, an element of the 2nd Brigade Combat Team, 4th Infantry Division was deployed to Forward Operating Base Duke, located in Najaf, Iraq, in support of Operation Iraqi Freedom.