In 1908, John Willys bought the Overland Division of Standard Wheel Cy and in 1912 renamed it Willys-Overland Motor Company. From 1912 to 1918, Willys was the second largest producer of automobiles in the United States after Ford Motor. In the mid 1920s, Willys also acquired the F.B. Stearns Company and assumed continued production of the Stearns-Knight luxury car as well. In order to raise cash needed to pay off debts, all of the Willys Corporation assets were on the auction block. The Elizabeth plant and the Chrysler Six Prototype were sold to William C. Durant, then in the process of building a new, third empire. The plant would build Durant's low priced Star, while the Chrysler Six prototype would be improved and modified, becoming the 1923 Flint.
Walter Chrysler moved on to Maxwell - Chalmers , where in January 1924 he launched his own version of the six-cylinder chrysler he had been working on, one still based partially on elements originally developed at Willys. (In 1925 the Maxwell car company would become the Chrysler Corporation).
In 1926, production of the Overland ended and was replaced by the Whippet brand of small cars. Following the stock-market crash of 1929 and the economic depression that soon followed, a number of Willys automotive brands began to falter. Stearns-Knight was liquidated in 1929. Whippet production ended in 1931, its models replaced by the Willys Six and Eight. Production of the Willys-Knight ended in 1933.
Production of the Willys MB, better known as Jeep, began in 1941, shared between Willys, Ford and American Bantam which had initiated the original Jeep body design. 8,598 units were produced that year, and 359,851 units were produced before the end of WW II. In total, 653,568 military Jeeps were eventually manufactured.