	Sommer was born in Mouzon, in the Ardennes "département" of France, into a wealthy Sedan carpet-making family. His father, Roger Sommer, broke the Wright Brothers' record for the longest flight in 1909. It was not until 1931 that Raymond started to display daredevil tendencies of his own, entering motor races in a privateer Chrysler Imperial. The following year, he won the 24 Hours of Le Mans race, despite having to drive over 20 hours solo after his teammate, Luigi Chinetti, retired ill. During the 1930s, Sommer was to dominate the French endurance classic, winning again in 1933 driving an Alfa Romeo alongside Tazio Nuvolari. He also led every race until 1938, only to suffer a mechanical failure, once when 12 laps in the lead. Sommer traveled to Long Island, New York, to compete in the 1936 Vanderbilt Cup where he finished fourth behind the winner, Nuvolari.