Boris Godunov is Modest Mussorgsky’s only completed opera, and is considered to be his masterpiece. Its subjects are the eponymous Russian ruler, who reigned as Tsar from 1598 to 1605, and the False Dmitry I, who succeeded him almost immediately but was killed only a year later. The Russian-language libretto was written by the composer, and is based on Pushkin’s blank verse drama Boris Godunov as well as Nikolay Karamzin’s History of the Russian...