Arms and the Man comes from Virgil's Aeneid, a famous epic poem about the founding of Rome. Shaw uses the Aeneid's opening line "Of arms [warfare] and the man I sing" ironically. While Virgil celebrates military valor, Shaw comically deflates it and shows would-be romantic soldier "heroes" like Sergius as bumbling and incompetent. The true "hero" of the play is Bluntschli, who climbs into Raina's bedroom one night as he deserts from the army, carrying chocolate rather than bullets in his pockets.
Shaw also puns on the double meaning of "arms." Arms are weapons, but they are also body parts, and lovers embrace using their arms. This is a love story as much as an anti-war play, in which Sergius is engaged to Raina, and the two pretend to have romantic love, but Raina's servant Louka is Sergius's true love. Many times he takes Louka into his "arms" to embrace her when Raina is not around. In the end, the proper lovers get sorted out in this light-hearted, if seriously themed, comedy.