Guillaume de Machaut, a leading French composer and poet of the 14th century, was born in Rheims and spent the greater part of his life there after earlier employment in the service of John of Luxemburg, King of Bohemia. He was employed subsequently by various members of the nobility, including the future Charles V of France. He held various church benefices and as a musician was pre-eminent in the period of music history known as the Ars nova, when composers created music of increased rhythmic complexity.