He then became a mining engineer in Vesoul and Nancy, but left that profession at the age of 29 to enter politics.

Re-elected in 1939, largely because of his record of accommodating all political sides, he exercised little power as president.

In June 1940, with the military collapse of France imminent, Lebrun wrote "the uselessness of the struggle was demonstrated.

"[1] With the Cabinet wanting to ask for an armistice, on 17 June 1940 Prime Minister Paul Reynaud resigned, recommending to President Lebrun that he appoint Marechal Philippe Pétain in his place, which he did that day.

[2] British General Sir Edward Spears, who was present with the French cabinet during this crisis wrote "it is clear that the President had made up his mind that France was free of her obligations to Britain, and was at liberty to ask for an armistice [with Germany] if she deemed it to be in her interests to do so.

[6] Lebrun fled to Vizille (Isère) on 15 July, but was captured on 27 August 1943, when the Germans moved into the region.