Manuel I Komnenos of the Byzantine Empire died on this day in 1180, marking the end of the Komnenos Restoration and the beginning of a terminal decline of power in the Empire. Byzantium, which had long been in decline and was constantly being defeated by Turkish and Muslim invaders by the beginning of the second millennium, saw a brief period of returned power and glory as the Komnenos family took over the Imperial throne, and began reconquering Byzantine lands from the Seljuk Turks. They were also heavily involved in the Crusades, with Manuel helping the Crusaders of the Second Crusade pass through his lands and found the Crusader States, including the Kingdom of Jerusalem. Byzantine interventions in the Balkans also helped to create Hungary as a regional power, under Byzantine influence. Manuel in his later years also attempted to reconquer the Byzantine lands in Anatolia, but partially due to his arrogance, was defeated by the Seljuks in a crucial battle, although he went on to win the war. Manuel also led a failed invasion of Sicily, but he did manage to secure an alliance with the Pope. Manuel died in the end of a fever, at the age of sixty-one. Byzantine power declined dramatically following his death, and Seljuk incursions into Byzantine lands continued, causing the fall of Byzantium in the fifteenth century and the rise of the Ottoman Empire.