Boris Godunov is a historical opera composed by Modest Mussorgsky, first performed in 1874. The opera is based on the play by Alexander Pushkin and tells the story of Boris Godunov, who becomes the Tsar of Russia after the death of Tsar Ivan IV. The narrative explores themes of power, guilt, and the struggles of leadership. The opera is notable for its rich orchestration and use of Russian folk melodies. It features a diverse cast of characters, including the mysterious Dimitri, who claims to be the rightful heir to the throne. The work is considered a significant contribution to the Russian operatic tradition.