Guillaume de Machaut was a medieval French poet and composer. He is regarded by many musicologists as the greatest and most important composer of the 14th century. Machaut is one of the earliest composers on whom substantial biographical information is available, and Daniel Leech-Wilkinson called him "the last great poet who was also a composer". Well into the 15th century, Machaut's poetry was greatly admired and imitated by other poets, including Geoffrey Chaucer.