The Medieval Period lasted from 800-1400 AD. Music during this time was mostly religious and associated with the Catholic Church. The primary musical form was Gregorian chant, which was single melodic line music popularized by Pope Gregory. Instrumental music involved instruments like organs, vielles, lutes, recorders and drums and was often used to accompany vocal music or dances. Major composers of the time included Guillaume Dufay, Phillipe de Vitry, and Guillaume de Machaut who helped transition Medieval music into the Renaissance period.