In 1939, the United States Army invited some 135 to 165 manufacturing companies to submit design proposals within a 75-day timeframe for a new multi-purpose logistical military vehicle to replace its aging fleet of motorcycles and Ford Model T trucks. Only three companies responded: Ford Motor Company, Willys-Overland and American Bantam Car Company. The initial contract went to Bantam, but their manufacturing limitations soon saw the US military hand over its plans to both Ford and Willys. New prototypes were then ordered from the remaining two companies to which Willys ultimately won a procurement contract in July of 1941. Ford Motor Company then agreed to build from the Willys design plan (as the "GP" for "Government Pygmy" based on its original vehicle submission to the US Army) and Bantam, sadly, was charged with nothing more than manufacture of Willys compatible trailers. Ford Willys vehicles were further designated "GPW" to indicate their Willys origins and were largely copies of the competing design. Between Willys and Ford Motor Company, 634,569 "jeeps" were produced during World War 2 (1939-1945).
The Ford mark was given the long form designation of "Government 80-inch Wheelbase Reconnaissance Car". The vehicle proved a compact, 4x4 wheel drive vehicle powered by a 4-cylinder gasoline-fueled engine running at 4,000rpm for hours on end. The engine was coupled to a three-speed manual transmission system with a four-wheel-drive transfer case and high / low gears. The vehicle was also issued with a fold-up cloth roof to protect occupants against the elements but offered little in the way of protection from battlefield dangers. The design could run on roads at speeds of 60 miles per hour, climb 40-degree slopes, achieve a turning radius of 30 feet and tilt up to 50-degrees to either vehicle side without tipping over. The Jeep was also converted into an amphibious car to ford water sources by way of a special boat-like hull fitted around the chassis and special attachments fixed into place for air intake and exhaust of the engine. This form failed to achieve much in the way of large-scale use.
During World War 2, American factories produced Jeeps in the tens of thousands. Lend-Lease saw the vehicles shipped to the inventories of the United Kingdom and the Soviet Union as well while many surplus forms in the post-war years were accepted into the Philippine Army (after major US forces withdrew from the Pacific island nation after the war) and elsewhere. Its reach was vastly global and the "go-anywhere" vehicle saw action throughout all major theaters of the war. At the peak of production, assembly lines turned out one vehicle every 90 seconds(!) As a result, the Jeep became something of a workhorse hero to the civilian-minded public. Demand for acquisition of the vehicle was high in the years following the war to the point that Willys continued production in large numbers. These civilian versions were designated as "CJ-2A" with the "CJ" standing for "Civilian Jeep".
The Jeep would go on to see combat duty in the Korean War as well as the Vietnam War in all degrees of conduct. In the post-war decades, the line continued in large-scale use with the US Army and was continually improved until 1981, by which time it had been formally replaced in inventory by other light vehicles and, ultimately, the High Mobility Multi-Purpose Wheeled Vehicle ("HUMVEE").
Official Jeep designations during World War 2 were Willys MA, Ford GP, Willys MB and Ford GPW. The Willys company produces over 363,000 examples whilst the Ford Motor Company produced over 280,000 jeep-types during the war. In all, hundreds of thousands of Jeeps of all types were produced, many versions solely differentiated visually by varying radiator grille arrangements.
During the early 1950s, the Willys M38 directly replaced the Jeep war-time models.