Pascal Collasse (or Colasse) (22 January 1649 (baptised) – 17 July 1709) was a French composer of the Baroque era. Born in Rheims, Collasse became a disciple of Jean-Baptiste Lully during the latter's domination of the French operatic stage. When Lully died in 1687 leaving his tragédie en musique Achille et Polyxène unfinished, Collasse completed the last four acts of the score. He went on to produce around a dozen operas and ballets, as well as sacred music, including settings of the Cantiques spirituels of Jean Racine. His plan to establish his own opera house in Lille ended in failure when the theatre burnt down. He dabbled in alchemy with even less success. His musical style is close to that of Lully.