Land was purchased in 1903, with the post being officially named for President Harrison in honor of Indianapolis being his hometown.
In 1901, former President Benjamin Harrison's son Russell, through lobbying efforts, sold a nearby U.S. Arsenal where the U.S. Army used the money to buy land where the fort is located today.

Fort Benjamin Harrison saw its highest level of activity during World War I and World War II.
 The Fort Benjamin Harrison Reception Center opened in 1941 and was the largest reception center in the United States by 1943.

Within Fort Harrison was Camp Glenn, named in honor of Major General Edwin Forbes Glenn, who had served as Fort Harrison's commandant from 1912–1913, and who commanded the officer training that began at his camps in 1916.
 Camp Glenn was a Citizens Military Training Camp (CMTC) that was also used to house Civilian Conservation Corps (CCC) workers.
 When the United States reestablished the Military Police Corps in 1941, an MP school was established at Camp Glenn and was operation by early 1942.
 The area was also used to detain Italian and German prisoners of war in 1944 and 1945.

In 1947, the Army declared Fort Harrison to be surplus property, but declined to completely close the fort due to a lack of adequate training space for the Indiana National Guard.
 From 1948 to 1950, the post functioned as Benjamin Harrison Air Force Base.
The Tenth Air Force was moved from Omaha, Nebraska and headquartered at Schoen Field on Fort Harrison, as well as Stout Army Air Field in Indianapolis.
 Overcrowding and inadequate facilities soon forced the 10th Air Force to move to Selfridge Air National Guard Base in Michigan, and the Army reacquired control of Fort Benjamin Harrison.

The U.S. Army Finance School was located at Fort Benjamin Harrison during the 1960s and '70s.

The Interservice Postal School was located at Fort Benjamin Harrison in the 1970s under the US Army Institute of Administration (USAIA), and was staffed by instructors from all four services.
 It moved to Fort Jackson in South Carolina in 1995.

Beginning in 1965, it was also home of the Defense Information School (DINFOS).
This was staffed by enlisted personnel and officers from all branches of the US military along with members of allied military personnel.
DINFOS trained service members and Department of Defense employees to become journalists in print, radio, television, and photography, as well as training them in advanced supervisory roles in editing, public affairs, and media and community relations.
In 1995, DINFOS moved to Fort Meade, Maryland.

With the movement and creation of a number of training classes in financial, clerical and information technology (most notably the Programmer/Analyst Course and the Computer Machine Operator Course) the fort was given the derisive moniker "Uncle Ben's Rest Home" implying that no real military training took place there.

The Fort was the site of the Athletes' Villages for the 1987 Pan American Games.
Construction documents were created for new buildings to house the athletes, but the buildings were not built.
Land was purchased in 1903, with the post being officially named for President Harrison in honor of Indianapolis being his hometown. In 1901, former President Benjamin Harrison's son Russell, through lobbying efforts, sold a nearby U.S. Arsenal where the U.S. Army used the money to buy land where the fort is located today.
Fort Benjamin Harrison saw its highest level of activity during World War I and World War II.  The Fort Benjamin Harrison Reception Center opened in 1941 and was the largest reception center in the United States by 1943.
Within Fort Harrison was Camp Glenn, named in honor of Major General Edwin Forbes Glenn, who had served as Fort Harrison's commandant from 1912–1913, and who commanded the officer training that began at his camps in 1916.  Camp Glenn was a Citizens Military Training Camp (CMTC) that was also used to house Civilian Conservation Corps (CCC) workers.  When the United States reestablished the Military Police Corps in 1941, an MP school was established at Camp Glenn and was operation by early 1942.  The area was also used to detain Italian and German prisoners of war in 1944 and 1945.
In 1947, the Army declared Fort Harrison to be surplus property, but declined to completely close the fort due to a lack of adequate training space for the Indiana National Guard.  From 1948 to 1950, the post functioned as Benjamin Harrison Air Force Base. The Tenth Air Force was moved from Omaha, Nebraska and headquartered at Schoen Field on Fort Harrison, as well as Stout Army Air Field in Indianapolis.  Overcrowding and inadequate facilities soon forced the 10th Air Force to move to Selfridge Air National Guard Base in Michigan, and the Army reacquired control of Fort Benjamin Harrison.
The U.S. Army Finance School was located at Fort Benjamin Harrison during the 1960s and '70s.
The Interservice Postal School was located at Fort Benjamin Harrison in the 1970s under the US Army Institute of Administration (USAIA), and was staffed by instructors from all four services.  It moved to Fort Jackson in South Carolina in 1995.
Beginning in 1965, it was also home of the Defense Information School (DINFOS). This was staffed by enlisted personnel and officers from all branches of the US military along with members of allied military personnel. DINFOS trained service members and Department of Defense employees to become journalists in print, radio, television, and photography, as well as training them in advanced supervisory roles in editing, public affairs, and media and community relations. In 1995, DINFOS moved to Fort Meade, Maryland.
With the movement and creation of a number of training classes in financial, clerical and information technology (most notably the Programmer/Analyst Course and the Computer Machine Operator Course) the fort was given the derisive moniker "Uncle Ben's Rest Home" implying that no real military training took place there.
The Fort was the site of the Athletes' Villages for the 1987 Pan American Games. Construction documents were created for new buildings to house the athletes, but the buildings were not built.
Fort Benjamin Harrison