The Excalibur was designed by Brooks Stevens while he worked at Studebaker. He was inspired by the 1928 Mercedes-Benz SSK and the first version became known as the "Mercebaker". It was built on a Studebaker chassis and powered by a 327 cubic inch V-8 Chevrolet engine that produced 300 horsepower. The Excalibur Automobile Corporation was established by Brooks Stevens' two sons, Steve and David, in 1964 and they sold their first car a year later.
The first car was a two-passenger roadster called the Excalibur SI and only a few hundred were made before production ceased in 1969. The Excalibur SII followed the next year with a totally new chassis and powertrain, offering additional amenities such as air conditioning. The Excalibur SIII followed in 1975, the SIV in 1980 and finally the SV in 1985. The cars were hand made at the rate of about five or six a week and they built about 3,500 vehicles over a 40 year period. The Excalibur sedans, limousines and other customized styles were most popular among movie stars and other celebrities.