Formed in 1906 to first produce automobiles, Rolls-Royce was asked to begin designing and building aircraft engines at the outbreak of World War I in 1914. Using experience from the high-output, liquid-cooled engines of the 1920s and '30s, which the organization helped pioneer, Rolls-Royce began design of the famous Merlin in 1933. Following its similar Kestrel design, the Merlin powered many significant aircraft of World War II, including the Hawker Hurricane, Supermarine Spitfire, and North American P-51.
The most powerful versions of the Merlin developed more horsepower for their displacement than any other World War II production engines. The Packard Motor Car Company and Continental Aircraft built over 58,000 Merlins in the United States under license. Many were shipped to England, and others used in versions of the American Curtiss P-40 and most versions of the P 51. This example of the Packard-built Merlin powered various models of the North American F-6 and P-51 Mustang.