He's able to capture significant portions of the West, including the Italian Peninsula. But then over time, the Byzantine Empire contracts. Especially in the East, it has to contend with the spread of Islam. As we go even further in time, as we enter into the second millennium, we can see that the Muslim Turks make further inroads into the Byzantine Empire. Also during the Fourth Crusades, Western crusaders sack Constantinople. And we can go all the way to 1453, where all that was left at the time of the Byzantine Empire, or you could say the Eastern Roman Empire, is Constantinople. And in 1453, that also gets sacked by the Ottomans.