Antoine de la Mothe Cadillac
Upon his arrival in America, La Mothe adopted his title after the town of Cadillac, Gironde in southwestern France. The city of Detroit became the world center of automobile production in the 20th century. William H. Murphy and Henry M. Leland founded the Cadillac auto company and paid homage to him by using his name for their company and his armorial bearings as its logo in 1902. Various places bear his name in America, in particular Cadillac Mountain in Maine and the town of Cadillac, Michigan.
Chuck Jordan (automobile designer)
One of his first projects was the Aerotrain, completed when he was 28 years old. He rose to director of design for Cadillac in 1957, being chief designer of the 1959 Cadillac, an epitome of fin design (although it was well underway when he arrived.) He also spent time with GM Europe as head of design for Opel. 
He was vice president of design for General Motors from 1986 to 1992. Only six people, including Harley Earl and Ed Welburn have held the position in GM's history.