Siegfried et le Limousin is a novel by Jean Giraudoux published in 1922 by Grasset.
In the story, Giraudoux explores the hostility between two warring countries, France and Germany, which underlies the tale of a man who has lost his memory.
A wound suffered in that war indeed caused Forestier to become an amnesiac, who then continued his life in Germany under a completely different name, unaware of his former identity.
The narrator goes to Munich, where he hopes to identify Forestier with the help of Baron von Zelten, a German diplomat serving in Paris.
In the end, Siegfried returns to Limousin, his former home in France, to resume his old life.