Ray Kroc was born in Chicago, Illinois, on October 2, 1902, the son of relatively poor parents. He went to public schools in Oak Park, Illinois, a suburb of Chicago, but did not graduate, leaving school to serve as an ambulance driver during World War I, like Ernest Hemingway, also from Oak Park. After the war Kroc became a jazz pianist, playing with the Isham Jones and Harry Sosnick orchestras. Upon his marriage in 1922 he went to work for the Lily-Tulip Cup Company, but soon left to become musical director for one of Chicago's pioneer radio stations, WGES. There he played the piano, arranged the music, accompanied singers, and hired musicians. Kroc's wanderlust was not satisfied with this, and the real estate boom in Florida soon found him in Fort Lauderdale selling real estate. When the boom collapsed in 1926 Kroc was so broke that he had to play piano in a night club to send his wife and daughter back to Chicago by train. He later followed them in his dilapidated Model-T Ford.
Kroc thereupon returned to Lily-Tulip as a salesman, later becoming midwestern sales manager. In 1937 he came upon a new invention, a machine that could mix five milk shakes at one time, called the "multi-mixer." Kroc founded his own company to serve as exclusive distributor for the product in 1941. Many years later, in 1954, Kroc heard of a drive-in restaurant in San Bernardino, California, owned by Richard and Maurice D. McDonald, which was operating eight of his multi-mixers. Curious as to how they could possibly use so many machines in a small establishment, Kroc found the brothers were doing a remarkable business selling only hamburgers, french fries, and milk shakes.
Kroc, from his years in the paper cup and milk shake business, recognized a potential gold mine and approached the brothers about starting a franchise operation based on their restaurant, selling hamburgers for 15 cents, fries for 10 cents, and shakes for 20 cents. After some negotiation the McDonald brothers agreed. Under the arrangement, they would receive one-half of one percent of the gross, Kroc would use the McDonald name and concept, pledged to retain high levels of quality, and would retain their symbol—the golden arches. Ray Kroc opened the first of the chain of McDonald's restaurants on April 15, 1955, in Des Plaines, Illinois.