In 1071, five years after Hastings, the Byzantine army, the oldest and best trained military force in Europe, was destroyed in battle with the Seljuq Turks at Manzikert in Armenia.

With this large but untrustworthy army Romanus set out in the spring of 1071 to reconquer Armenia. As he was leaving the capital the news came through from Italy that Bary, the last Byzantine possession in the peninsula, had fallen to the Normans.
The chroniclers tell in tragic detail of the Emperor's march eastward along the great Byzantine military road. His intention was to capture and garrison the Armenian fortresses before the Turkish army should come up from the south. Alp Arslan was in Syria, near Aleppo, when he heard of the Byzantine advance. He realized how vital was the challenge; and he hurried northward to meet the Emperor. Romanus entered Armenia along the southern branch of the upper Euphrates. Near Manzikert he divided his forces.

In the battle of Manzikert, or Malasgard, in Armenia, the Seljuk Sultan Alp Arslan defeated Emperor Romanus

The fate of Anatolia was decided in 1071 by the battle of Manzikert, in the highlands of Armenia, where the Seljuk sultan Alp Arslan inflicted an overwhelming defeat on the Byzantine army and took the emperor prisoner.

In the battle of Manzikert, or Malasgard, in Armenia, the Seljuk Sultan Alp Arslan defeated Emperor Romanus IV, took him prisoner, and destroyed most of the Byzantine army. As a result of this battle, the Turks won Asia Minor.