It's hard to believe, but America's most iconic 4x4 is turning 75 today.

On April 7th, 1942, the U.S. Patent office awarded a patent for the military vehicle that would later become known as the Jeep.

As I understand it, the truck was commissioned by the U.S. military when it became obvious that America would be drawn into World War II. The two companies to bid for the job were then-bankrupt American Bantam Car Company and Willys-Overland.

Based upon the cheap but rough-and-tumble vehicle it came up with, Bantam was awarded the contract. Since the Bantam's engine didn't make enough torque, the military specified the Willys engine for the final product.

Turned out, though, still-bankrupt Bantam was too small an outfit to produce such a vehicle en masse. So the government gave production duties to larger Willys and Ford — with the Willys engine onboard.

A body swings over the line before the previous one is out of the way, wheels and tires rolling down in background, in Willys-Overland Motor plant at Toledo, Ohio on June 19, 1942. They will be installed further down the line. (AP Photo) Image: ASSOCIATED PRESS

Ford designated the truck the GPW — G for government use, P designated its 80-inch wheelbase and W for the Willys engine. This is where one theory on the origins of the Jeep moniker come from: a shortened nickname for GPW slurred into "Jeep."

Another theory suggest that the military personnel were so impressed with the truck's capability that they named it after Eugene the Jeep from the Popeye comic strip, who could famously climb over everything.

No matter how it gained the name, it stuck and lives on as the Jeep brand. The shape lives on, too, as the Wrangler.

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