Charles Léon Claude Daniélou came from a prosperous Breton family with the strong tradition of political activity.

His grandfather, Jean-Pierre Daniélou (1798–1864), was a notary in Locronan and then Douarnenez, where he was mayor during the French Second Republic from April 1848 to January 1949.

His father, Eugène-Lucien-Napoléon Daniélou (1834–1897) was a wealthy wine merchant and one of the leading businessmen in Douarnenez, where he was several times mayor between 1855 and 1896.

He began writing poetry, and in 1897 sent a copy of his first collection of poems to François Coppée, who invited him to come to Paris.

He met literary and political figures such as Henri de Régnier, Pierre Louÿs, Gabriel Hanotaux, Louis Barthou, Georges Leygues, Émile Zola and Sarah Bernhardt.

Daniélou sided with Coppée and helped found the anti-Dreyfus Ligue de la patrie française in December 1898.

[5] After their marriage the couple settled in Locronan, where Charles Daniélou was elected as a municipal councilor in 1908, running as an Independent Republican.

There were six children from the marriage including Jean Daniélou, who became a Catholic cardinal and Catherine, wife of Georges Izard.

He introduced a bill to ensure that sailors had religious freedom and another to provide subsidies for repairing school buildings.

On 19 April 1921 the prime minister Aristide Briand appointed him "commissioner for French expansion abroad.

[6] The official biography in the Dictionnaire des parlementaires français (1889–1940) records that Daniélou was noticed by François Coppée when he was 21, and published his first collection of verse, Ascension, in 1903.