Marcel Mathieu René Leccia was born on 1 January 1911. His father was a colonel in the French army and Leccia was partly brought up in the French-occupied Rhineland, where he became fluent in German. After his national service he worked for a time as a Renault car salesman and married a woman named Alice Beitz - the couple had two children but later divorced. Then in August 1939, with World War Two looming, he was called up to the army as a 2nd lieutenant.