most historical records. Due to his continuous military successes the Byzantine empire was kept safe and its realms were free from destruction and allowed to grow and prosper. During this time John also reorganized the Byzantine army, making it into a professional fighting force, and not the hodge podge of local forces it had been previously. He created permanent, fortified military camps in both Anatolia and the Balkans, where his field armies could be concentrated and trained, and added a large cavalry component to the army (most famously the Kataphraktoi of Macedonia) which allowed the Byzantines to effectively fight the more mobile Turks. Yet John died suddenly in 1143, possibly from a poison arrow treacherously sent to him by jealous crusaders who did not want him to succeed and encroach on their territory or sovereignty. His sudden death kept the Byzantines from continuing their conquests of Anatolia, and historian Zoe Oldenbourg believes that, if John had lived but a few more years, much larger territorial gains would have been made by the Byzantines. Manuel I Komnenos (1143–1180) Though Manuel was the youngest of John's four sons he was chosen to succeed his father due to his ability to listen to advice and learn from his mistakes (or so his father discerned). He continued the Komnenian restoration admirably, particularly in the Balkans where he consolidated Byzantine holdings and inflicted a crushing defeat on the Kingdom of Hungary in 1167 at the Battle of Sirmium. With this victory the Kingdom of Hungary was made a vassal of the Empire and, according to noted Byzantine historian Paul Magdalino, Byzantine control over the Balkans was at its most effective point since Late Antiquity. Additionally Manuel opened up relations with the Western powers as he was a man who loved all things Western European and even organized regular jousting competitions. Because of this fondness, he increased diplomatic ties to the West, arranging alliances with the Pope and the Crusaders of the Outremer and successfully dealt with the troublesome Second Crusade that passed through his lands. Conversely, Western Europeans held him in great esteem, and he was described by the Latin historian William of Tyre as "beloved of God...a great-souled man of incomparable energy," highlighting the goodwill he garnered with the previously hostile Western European powers. Indeed, of all the Byzantine emperors it is said that Manuel was the closest to healing the centuries-old rift between