Answer:
The Mongols
Explanation:
The Mongols invaded a large part of the Muslim world during the 12th century. They came from Central Asia, and after subjugating China, they posed their eyes in the Muslim world and Europe.
Two important cities were sacked by the Muslim armies: Sarmakand, in Central Asia (in what is now Uzbekistan), and Baghdad. The case of Baghad was even more dramatic because the city was not only sacked, but also destroyed. Baghdad was at the time, the most important city of the Muslim world, and it never regained the same splendour after this event.
