Richelieu; Or the Conspiracy (generally shortened to Richelieu) is an 1839 historical play by the British writer Edward Bulwer-Lytton. It portrays the life of the Seventeenth Century French statesmen Cardinal Richelieu.
The play has become best known for its line "The pen is mightier than the sword", spoken by the Cardinal in Act II, Scene II.
The play formed the basis of a 1935 American film directed by Rowland V. Lee and starring George Arliss as Richelieu. It was produced by 20th Century Pictures.