When the United States joined World War II following Japan’s attack on Pearl Harbor on December 7, 1941, manufacturers of all types of goods were called upon by the government to retool to build items needed for victory against the Axis powers. This of course included automakers, who had factories well suited for producing war-time vehicles. Despite its background in luxury automaking, Cadillac became a vital component of the manufacturing process. Among the items to come out of Cadillac plants during World War II were M24 Light Tanks. They first started building them in April 1944. Agricultural equipment maker Massey-Harris (now Massey Ferguson) began production that July. By the time production ended on this day in 1945, the two companies built 4,731 M24s.