The Nash 600 is an automobile that was manufactured by the Nash-Kelvinator Corporation of Kenosha, Wisconsin for the 1941 through 1949 model years, after which the car was renamed the Nash Statesman. The Nash 600 was positioned in the low-priced market segment. The '600' name comes from the car's ability to go 600 miles (970 km) on one tank of gasoline. Introduced for the 1941 model year, the Nash 600 became the first mass-produced unibody constructed car built in the United States.
The Nash 600 is generally credited with being the first mass-produced American automobile that was constructed using unitized body/frame construction techniques in which the car body and the frame are welded as one unit, rather than the more traditional body-on-frame (the body is bolted to the frame) method. Unitized construction allowed Nash to advertise that the car was lighter in weight, quieter, and more rigid than its competitors. Elimination of the frame in favor of a combined body-and-chassis construction reduced the car's weight by 500 pounds (230 kg).
Ambassador was the model name applied to the senior line of Nash automobiles from 1932 until 1957. From 1958 until the end of the 1974 model year, the Ambassador was the product of American Motors Corporation (AMC), which continued to use the Ambassador model name on its top-of-the-line models, making it "one of the longest-lived automobile nameplates in automotive history."
From 1927 through the mid-1932 model year, the Ambassador name was applied to a high trim club sedan body style, one of Nash's most prestigious senior models. The Ambassador series was the "flagship" in the Nash line.
Nash Motors' first use of the name Ambassador was during the 1927 model year when a specially trimmed four-door, five-passenger club sedan version of the "Nash Advanced Six" (designated model 267) was developed. As the most expensive car in the line, the Ambassador received premium upgrades in upholstery and other trim items for a base price of US$2,090 (FOB).