ARNULF (85o?-899), Roman emperor, illegitimate son of Carloman, king of Bavaria and Italy, was made margrave of Carinthia about 876, and on his father's death in 88o his dignity and possessions were confirmed by the new king of the east Franks, Louis III. He did homage to the emperor Charles the Fat in 882, and spent the next few years in constant warfare with the Slays and the Northmen. In 887, however, Arnulf identified himself with the disgust felt by the Bavarians and others at the incapacity of Charles the Fat. Gathering a large army, he marched to Tribur; Charles abdicated and in 888 the Germans recognized Arnulf as their king, a proceeding which L. von Ranke describes as "the first independent action of the German secular world." Arnulf's real authority did not extend far beyond the confines of Bavaria, and he contented himself with a nominal recognition of his supremacy by the kings who sprang up in various parts of the empire. He continued the struggle with the Northmen in 891, and gave effective aid to Zvatorpluk, king of Moravia, in his struggle with the nobles. Invited by Pope Formosus to deliver him from the power of Guido III., duke of Spoleto, who had been crowned emperor, Arnulf went to Italy in 894, but after storming Bergamo and receiving the homage of some of the nobles at Pavia, he was compelled by desertions from his army to return. In the next three years he succeeded in establishing his illegitimate son, Zwentibold, as king of the district afterwards called Lorraine. The restoration of peace with the Moravians and the death of Guido prepared the way for a more successful expedition in 895 and Arnulf was crowned emperor by Formosus in Feb. 896. He then set out to establish his authority in Spoleto, but on the way was seized with paralysis. He returned to Bavaria, where he died in Dec. 899, and was buried at Regensburg. He left, by his wife Ota, a son Louis surnamed the Child.
See "Annales FuIdenses" in the Monumenta Germaniae historica. Scriptores, Band i. (Hanover and Berlin, 1826) ; M. J. L. de Gagern, Arnulfi imperatoris vita (Bonn, 1837) ; E. Dummler, De Arnulfo Francorum rege (1852) ; W. B. Wenck, Die Erhebung Arnulfs and der Zerfall des karolingischen Reiches (Leipzig, 1852) ; E. Muhlbacher, Die Regenten des Kaiserreichs unter den Karolingern (Innsbruck, 1881) ; E. Dummler, Geschichte des ost f rdnkischen Reichs (Leipzig, 1887-88) ; 0. Dietrich, Beitrtlge zur Geschichte Arnolfs von Kdrnthen and Ludwigs des Kindes (189o) .