The Black Arrow by R. L. Stevenson

During England’s Wars of the Roses, young Richard Shelton’s loyalty to his guardian, Sir Daniel Brackley, is shattered when he learns that Sir Daniel may have murdered his father.

Alerted by a mysterious outlaw fellowship called “The Black Arrow,” Dick is forced to flee, and joins the outlaws, falling in love with the disguised Joanna Sedley,—and fights for revenge, honor, and justice in the midst of a bloody civil war.