John was transferred to Fitzsimmons Army Hospital in April 1941. The facility was founded by the U.S. Army during World War I arising from the need to treat large numbers of casualties from chemical weapons in Europe.

 

Army Hospital 21, as it was first called, was formally dedicated in the autumn of 1918. In July 1920, the facility was formally renamed the Fitzsimmons Army Hospital after William T. Fitzsimmons, the first American medical officer killed in World War I. A new main building, known as Building 500 was built in 1941.

 

At the time it was the largest structure in Colorado at 10 stories high with 606 beds. The new building featured a cream-colored brick exterior with an entrance of white Colorado marble. The facility was used heavily during World War II to treat returning casualties and it became one of the Army’s premier training centers.

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