During World War II, the great-grandson of John Deere, Charles Deere Wiman, was president of the company, but he accepted a commission as a colonel in the U.S. Army. A replacement was hired and before returning to work at the company in late 1944, Wiman directed the farm machinery and equipment division of the War Production Board. In addition to farm machinery, John Deere manufactured military tractors, and transmissions for the M3 tank. They also made aircraft parts, ammunition, and mobile laundry units to support the war effort.