John Davenport Siddeley, Baron Kenilworth (August 5, 1866-November 3, 1956), was a poineer of the automobile industry in the United Kingdom.

Siddeley founded the Siddeley Autocar Company in 1902. It was purchased by Wolseley of Coventry and Siddeley became the manager Wolseley-Siddeley. He resigned from Wolseley in 1909 to manage the Deasy Motor Company. In 1919, Siddeley-Deasy was merged with Armstrong-Whitworth to become Armstrong Siddeley.