Jan Pieterszoon Sweelinck (May 1562 – October 16, 1621) was a Dutch composer, organist, and pedagogue whose work straddled the end of the Renaissance and beginning of the Baroque eras. Sweelinck was a master improviser, and acquired the informal title of the "Orpheus of Amsterdam". Over 70 keyboard works of his have survived, and many of them may be similar to the improvisations that residents of Amsterdam around 1600 were likely to have heard. Even his vocal music, which is more conservative than his keyboard writing, shows a striking rhythmic complexity and an unusual richness of contrapuntal devices.