The Three Musketeers (French: *Les Trois Mousquetaires)*was first serialized in March-July 1844. Set in the 17th century, it recounts the adventures of a young man named d'Artagnan as he goes to Paris to join the Musketeers of the Guard. There he meets the musketeers of the title; his friends Athos, Porthos, and Aramis, who live by the motto "all for one, one for all" ("un pour tous, tous pour un"), a motto which is first proposed by d'Artagnan.
The story of d'Artagnan is continued in Twenty Years After and The Vicomte of Bragelonne: Ten Years Later. Those three novels by Dumas are together known as the d'Artagnan Romances.
D'Artagnan was a real historical figure and the novel was inspired by his memoirs, though it does not follow them closely.
The Three Musketeers was first published in serial form in the newspaper Le Siecle between March and July 1844.