On August 1, 1941, the first Jeep was produced. From the article:
“As faithful as a dog, as strong as a mule and agile as a goat.” – Ernie Pyle (referring to the Jeep) "Jeeps were used by every service of the U.S. military. An average of 145 were supplied to every Army infantry regiment. Jeeps were used for many purposes, including cable laying, saw milling, as firefighting pumpers, field ambulances, tractors and, with suitable wheels, would even run on railway tracks. An amphibious jeep, the model GPA, or “seep” (Sea Jeep) was built for Ford in modest numbers but it could not be considered a huge success—it was neither a good off-road vehicle nor a good boat. As part of the war effort, nearly 30% of all Jeep production was supplied to Great Britain and to the Soviet Red Army. WWII Jeeps Put thru their paces “Autobiography of a Jeep” Final production version Jeeps built by Willys-Overland were the Model MB, while those built by Ford were the Model GPW (G=government vehicle, P designated the 80″ wheelbase, and W = the Willys engine design). There were subtle differences between the two. The versions produced by Ford had every component (including bolt heads) marked with an “F”. Willys also followed the Ford pattern by stamping its name into some body parts, but stopped this in 1942. The cost per vehicle trended upwards as the war continued from the price under the first contract from Willys at US$648.74 (Ford’s was $782.59 per unit). Willys-Overland and Ford, under the direction of Charles E. Sorensen (Vice-President of Ford during World War II), produced about 640,000 Jeeps towards the war effort, which accounted for approximately 18% of all the wheeled military vehicles built in the U.S. during the war. “The spartan, cramped, and unstintingly functional jeep became the ubiquitous World War II four-wheeled personification of Yankee ingenuity and cocky, can-do determination.” – Doug Stewart"
Read more:
http://www.ibov.org/2015/august-1-1941-first-army-jeep-produced/