The activities of Norman chiefs in Asia minor at 11th century

The Normans conquered almost Europe until the end of the 12th century. After Basil II dead in 1025 Byzantine declined because of military, fiscal, and administrative problems; the Seljuk Turks expanded their conquest area to central of Asia Minor. Byzantine began to use the Normans as mercenary to strengthen Byzantine army against new power, which was Turks, in Asia Minor in the 11th century. Hervé Frankopoulos arrived to Istanbul and attended to Byzantine army in the first half of the 11th century. He revolted against imperial government because the emperor refused to give some titles him for his victories. After Hervé?s uprising his follower, who was Robert Crispin, arrived at the capital of the empire and fought in the service of Romanos Diogenes against Turks in Syria. Because he did not take promptly his price and titles from Diogenes he rebelled against Byzantine government in Giresun. He was exiled by emperor after his uprising. Michael Doukas recalled the Norman chieftain from exile and used him in the campaign against Diogenes. Roussel de Bailleul, who fought with Diogenes against Seljuks in battle of Manzikert, rose up against Byzantine. Roussel got a great territory under control in the Eastern Anatolia and Black Sea Region. He gained ground with his soldiers so far Istanbul and left Byzantine in a difficult situation. Byzantine made an alliance with Seljuks to stop Roussel?s progress. So that Roussel?s rebellion, which occupied Byzantine for a long time, was concluded by help of Seljuks.