Evacuation Hospital #15 earned a battle streamer for its participation in the Meuse-Argonne Forest offensive from 26 September 1918 through 11 November 1918.

The hospital, having served honorably and proud during World War I, returned to the United States aboard the "S.S. America" and was demobilized at Camp Lewis, Washington on 28 June 1919.

As the first hostilities of World War II began, the 15th Evacuation Hospital was again activated in a training status at Fort George G. Meade, Maryland.

On 21 February, the ship docked in Algeria, where the 15th unloaded its men and equipment and went into a staging area to await its first operational assignment.

On 10 April 1943, the unit moved a distance of approximately 600 miles east to Tunisia, where it set up and began receiving patients.

At this point, the hospital sailed for the southern coast of Sicily, where it supported the beach-head established by allied forces.

The hospital's comparatively comfortable life in Rome was short-lived, and on 21 June 1944, the 15th moved north in support of combat operations through Florence and the Po Valley into Milan, where it served until the end of hostilities.

In addition to several campaign streamers, including: Tunisia, Naples-Foggle, Rome-Arno, Po Valley, and North Apennines, the 15th Evacuation Hospital received the most prized award of all, the Meritorious Unit Citation, for its outstanding performance during World War II.

The 15th Evacuation Hospital was again reactivated on 25 August 1959, at Nuremberg, Germany, where it was responsible for the medical care of military and civilian personnel.

On 1 August 1968, the 15th Evacuation Hospital arrived at Fort Belvoir, Virginia after being airlifted from Rhein Mein Air Base, Germany during a period of troop reduction in Europe.

On 31 July 1975, the 15th Combat Support Hospital was alerted for deployment to Fort Indiantown Gap, Pennsylvania for the purpose of operating the Medical Treatment Facility, Task Force New Arrivals, providing comprehensive medical care to Indochinese refugees and task force personnel, both military and civilian.

The 115th CSH provided level one, two and three health service preventive medicine support, while also leading a medical task force more than 400 strong that spanned the southwestern and western regions of Afghanistan.

115th Combat Support Hospital training deployments during this time included numerous JRTC rotations, Partnership for Peace exercises, a Bright Star rotation in Egypt, Operation Rolling Thunder, Operation Team Spirit, MEDEX 2000 in Japan and various other exercises.

After the end of World War II in Europe, the unit was inactivated on 15 November 1945 at Camp Myles Standish, Massachusetts.

During WWII the unit earned Campaign Participation Credit in Normandy, Northern France, Rhineland, Ardennes-Alsace, and Central Europe.

The 485th Medical Detachment proudly answered its nation's call when needed, and deployed to: Lebanon (1958), Iran (1962), Morocco (1963), Yugoslavia (1963), Arkansas, Texas, Louisiana and Oklahoma (1971), Arkansas and Pennsylvania (1975), Colorado (1976), Somalia (1993), Surinam (1994), and Operations Spartan Shield and Inherent Resolve (2017).

After being inactivated in China on September 20, 1945, it was redesignated as Headquarters, 43rd Veterinary Service Detachment and attached to the Regular Army on August 13, 1951.

Inactivated in France on February 23, 1967, it was subsequently reactivated at Fort Sam Houston, Texas, on May 26, 1967, and deployed to Vietnam.

After being inactivated in Vietnam on December 26, 1971, it was reactivated at Fort Hood, Texas, on October 1, 1993, as the 43rd Medical Detachment (Veterinary Services).

The 33rd Optical Detachment deployed to Iraq from 19 September 2009 to 3 August 2010 as a part of Iraqi Sovereignty and again from 19 April 2015 to 31 December 2015 to Kuwait in support of Operations Inherent Resolve, Spartan Shield, and Freedom's Sentinel.

The unit was stationed at Fort Polk, LA until its deactivation on 3 August 2018. p The 115th Combat Support Hospital was featured on LT. Col Oliver North's "NRAs Life of Duty" while serving in Afghanistan in 2011.