Designated King of Italy 839 and crowned king at Rome by Pope Sergius II 15 June 844; in 850 crowned joint emperor at Rome by Pope Leo IV; on the death of his father in 855 became sole emperor; involved with his brother Lothair's divorce proceedings; in 863 received the kingdom of Provence on the death of his brother Charles; with help of Basil I fought against the Saracens who were ravishing southern Italy, but could not follow up his successes for want of a fleet; crowned a second time as emperor by Pope Adrian II 18 May 872; won further victories against the Saracens; named as his successor his wife's brother Carloman, son of Louis the German.