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The Byzantine Emperor John II Comnenus fought against the Danishmend emir of eastern Anatolia with varying degrees of success. His most famous expedition against them was a war which led to the siege of Neocaesaria (Niksar) in 1139-1140. The siege failed, but what it he had been able to capture Niksar, which I believe at the time was the capital of the Danishmend emirate.
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