One of the consequences of the Mongol conquests in the 13th cent. was to drive a certain tribe of Turks, which came to be known as the Ottoman Turks, out of  Turkestan into Asia Minor.

Turkish warriors flocked to the service of the Ottoman sultan from all over the Muslim world, because his holy war against the Byzantine Christians made religious merit and heroic exercise of violence coincide, as was true nowhere else in the Muslim world. Under these conditions, the  Ottoman Empire, (established in 1301), advanced rapidly until it spread all the way from the Euphrates to the Danube. (see Map)

Unlike the Arabs, who thought the use of firearms dishonorable, the Ottomans became masters of artillery. In  1453 they brought their cannons to  Constantinople. The fall of Constantinople was a defining event and marks the end of the European Middle Ages