On 26 August 1071, the Battle of Manzikert initiated the decline of the Byzantine Empire. The Byzantine emperor, Romanos IV Diogenes, troubled by Turkish Seljuk incursions into Byzantine Anatolia, mobilized a large army on his empire’s eastern borders, from which he entered Turkish-controlled Armenia. Once he reached the town of Manzikert, Diogenes split his army, with a small contingent camping outside the Manzikert city walls. His adversary was the second sultan, Alp Arslan, of the Great Seljuk Empire, which controlled much of the Near East. Arslan, acting on intelligence from Diogenes’ Turkish mercenaries, intercepted the main Byzantine contingent with his horse archers. The Seljuks then surrounded the advancing Byzantine main body, who attempted to disengage, panicking under the continuous Seljuk arrow onslaught. The smaller contingent failed to cover the retreating main body and Diogenes was wounded and captured. He was released only after he ceded Byzantine Anatolia.
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