The Copperhead is a 1920 American silent historical drama film based on a novel by Frederick Landis and a 1918 play by Augustus Thomas.

The star of this film is Lionel Barrymore who won acclaim in the play version on Broadway, and who appeared in the play and this film with his first wife Doris Rankin.

At the beginning of the American Civil War Milt Shanks, who owns a farm in Illinois, is asked by President Abraham Lincoln to join the Copperheads, a clandestine quasi-political organization whose sentiments lie with the South.

His family and friends unknowing of his mission call him a traitor.

Shanks spends decades keeping silent about his involvement with the Copperheads until his granddaughter prepares to marry and he's forced to come clean about being involved in a secret Civil War Mission.