Ok Dip Shit here is your history lesson.
"The Jeep legend began in November 1940, in the early days of World War II, just a year before the United States entered the war. A small, four-wheel drive prototype, the Willys "Quad", was delivered to the US Army. It featured the Willys "Go-Devil" engine, developed by Delmar "Barney" Roos. With 60 horsepower and 105 foot-pounds of torque it not only exceeded the Army's requirement, but dwarfed the Bantam's 83 and Ford's 85 pound-feet of torque, it's only competitors for the military contract. The Quad was the father of the MB, CJ series, and Wrangler. Willys refined the Quad and built 1,500 units of the Willys MA model, many of which were used in WWII.
From 1941 to 1945 Willys produced the MB model, the original go-anywhere, do-anything vehicle, which came to be known by its nickname, "Jeep". Made famous during WWII, Willys produced over 300,000 MB vehicles. Jeeps were heavily used by every division of the American military, with 144 Jeeps provided to every infantry regiment in the U.S. Army. Large numbers of Jeeps were shipped to the Allied Forces of Britain and Russia: nearly 30% of total Jeep production.
The MB evolved into the M-38 military model, which featured a waterproof ignition system and was built from 1950 to 1951 specifically for use during the Korean War. During that conflict, Willy redesigned the M-38 and it became the M-38A1 with a longer wheelbase, softer ride, a more powerful engine and a new, more rounded body style. In production through 1962, during that time Willys also produced the M-170, which was designed to be fitted with several different body packages. One was a light troop carrier. Because passengers were somewhat enclosed compared to earlier models, the M-170 was also used as a field ambulance. Kaiser Willys Auto Supply has old Jeep parts for all Willys military Jeep models."
And this
"It all began in 1940, when the Bantam Pilot was delivered to the US Army for consideration as a light 4x4 reconnaissance and scout vehicle. Powered by a 45-horse Continental four-cylinder engine and with a curb weight of 2,030 pounds, the little Bantam Pilot and 69 subsequent Bantam BRC-60 prototypes whetted the Army's appetite and proved the viability of the concept. An open bid was issued and ultimately Willys, Ford, and Bantam slugged it out with prototypes of their own.
The year 1941 saw production of "pre-standardized" jeeps from all three manufacturers. Ford cranked out roughly 4,458 GPs, Bantam with 2,605 BRC-40s, and Willys with 1,555 MAs. It was from the strengths of these three pre-standardized vehicles that the Army developed its criteria for its "standardized" jeep, which Willys would build during the remainder of the war as the MB and Ford would build as the GPW. The smaller Bantam company would build the trailers towed into combat by the little 1/4-ton vehicles, as well as other parts and components for the war effort."
ADDED: That is why most people think of Willys when they think of antique Jeeps.