Camp Grant was opened just south of Rockford in 1917 to train soldiers for World War I. It was closed in 1921 and turned over to the Illinois National Guard for use as a training center in 1924.
In October 1940 Camp Grant was re-activated as an induction center, being transferred by Illinois back to the federal government and closed 15 October 1944. The overall training activities lasted from 15 March 1941 to 30 September 1944. In June 1944 the MRTC activities were transferred to Ft. Lewis, Tacoma, Washington. 
Physical exams and medical training post for draftees was the main focus, although a fair number of personnel went through Camp Grant for their Army basic training. It is estimated that 100,000 medical corpsmen were trained at the camp. During the war Camp Grant also served as a POW detention center, employing upwards of 6,000 civilians, boosting Rockford's economy. It is estimated there were 2,500 POWs in the camp. After the war Camp Grant also served as a separation center for returning GIs.
In 1946 Camp Grant was permanently closed. The Chicago Rockford International Airport occupies much of the land that used to be Camp Grant. For a few short years after the war the barracks buildings of Camp Grant were converted into make-shift apartments. These 'homes' were utilized by returning GIs that had young families. By the late 1940s many of Camp Grant's buildings were torn down and residents moved out. In the 1950s much of the remaining camp land was in the possession of Seth B. Atwood, who would later donate former Camp Grant rifle range to the Rockford Park District, who would name it the Seth Atwood Park.
