Ottoman Empire

Last known classical empire in European and Middle Eastern history. Founded by a turkish warchief in the early 14th century, it quickly thrived in Anatolian border of Seljuk Sultanate and Eastern Roman Empire(Or what's left of it). They thrived almost without a halt for around 2 centuries, mixed the classical nomadic mounted cavalry system with roman infantry influences, and with great prowess at firearms. Conquered considerable amount of land and continued the relentless turkic expansion upon western soils, and unlike their predecesors like huns, or mongols, they managed to stay at where they held their grasp for at least a considerable amount of time. At its peak, the Empire held Anatolia, most Southeastern Europe, Eastern Coastlands of the Adriatic Sea, Greece, North Africa, Western territories of Iran, all muslim lands between the Persian Gulf and the Redsea and Crimean Peninsula up north. The infamous Mehmed the 2nd, known as the Great Conqueror even managed to make a foothold at Otranto, Italy. Capturing the city and starting his campaign to make the Ottomans the one and only successors of Roman Empire. They started to decline after European nations' swift intellectual, political and scientifical rise around 15th century. They struggled internally, never understood capitalism, never managed to adapt mass production and tried to reliy military based Romelike regime for far too long until the inevitable westernization.