favour. By 832 he was reinstated in the Abbey of Saint-Denis, whereupon he apparently withdrew from politics and successfully undertook a reform of that monastery according to the Benedictine rule. When the King's sons again rebelled the following year, Louis and his young son Charles were brought from Soissons and held at Saint-Denis for a few weeks. The King was restored to power at Saint-Denis in March 834. Upon the death of Louis the Pious in 840, Hilduin supported the King's eldest son Lothair I against his brothers Louis the German and Charles the Bald. With the division of the kingdom pursuant to the Treaty of Verdun in 843, Saint-Denis fell in the territory of Charles. Hilduin resigned as abbot, and Lothar appointed him to the archbishopric of Cologne, but he was never consecrated as archbishop. When not residing in Cologne, he frequently served as ambassador from Lotharingia to Constantinople. Works In 835, Louis commissioned Hilduin to write a biography of St. Dionysius of Paris, the emperor's patron saint. Hilduin executed this commission, with the aid of the pseudo-Dionysius's writings, a copy of which had been sent to the Frankish court by the Byzantine Emperor Michael II, and of other authorities. In his "Vita" Hilduin identified Dionysius of Paris with the Areopagite Dionysius, a view not generally accepted at that time, but which Hilduin's biography popularized for several centuries, until Sismondi and others dispelled this error. Hilduin also helped to complete the Carolingian "Reichsannalen", or imperial annals. In 1940, Max Buchner identified Hilduin as the author usually referred to as "The Astronomer," the author of the Vita Hludovici, a biography of Louis. This theory has achieved some popularity amongst later scholars, notably Ernst Tremp in 1995. References Bibliography 780s births 850s deaths French abbots Bishops of Paris Bishops in the Carolingian Empire Frankish historians Historians from the Carolingian Empire 9th-century Latin writers