Music in Belarus largely comprises a rich tradition of folk and religious music. The country's folk music traditions can be traced back to the times of the Grand Duchy of Lithuania. In the 19th century, Polish composer Stanisław Moniuszko composed operas and chamber music pieces while living in Minsk. During his stay, he worked with Belarusian poet Vintsent Dunin-Martsinkyevich and created the opera ''Sialanka'' (''Peasant Woman''). At the end of the 19th century, major Belarusian cities formed their own opera and ballet companies. The ballet ''Nightingale'' by M. Kroshner was composed during the Soviet era and became the first Belarusian ballet showcased at the National Academic Vialiki Ballet Theatre in Minsk.