Answer:
The Seljuks.
Explanation:
The Seljuk are a people of Turkic origin. Armies of the Seljuk Empire clashed with the forces of the Byzantine Empire at the Manzikert Plains on August 26, 1071 AD. The Byzantine army was crushed and slaughtered by the victorious Seljuks. Emperor Romanos IV Diogenes was taken captive. The Byzantine strength was seriously weakened and Turkmens took control of Anatolia, where they spread.
