Trained as a paleographer and archivist, he brought to his works a spirit of objectivity and a scrupulous regard for detail, and because of his concern with documentation and the relationship of social reality to individual development, his fiction has been linked with the realist and naturalist traditions of the 19th century.

Written under the shadow of the darkening international situation in Europe in the 1930s, these last parts, which together are longer than the previous six combined, focus on the political and historical situation leading up to the outbreak of the First World War and bring the story to 1918.

Du Gard wrote several other novels, including Jean Barois, which was set against the historical context of the Dreyfus affair.

During World War II, he resided in Nice, where he prepared a novel (Souvenirs du lieutenant-colonel de Maumort) which remained unfinished at his death.

His other works include plays and a memoir of André Gide, a longtime friend.