Years ago I read A Short History of Byzantium by John Julius Norwich. More than anything else that book sparked my desire to visit Istanbul and the rest of Turkey, which I did in 2000. If you're like me, your education taught you "Rome" ended in the 5th century. No! While the west was ransacked and fractured by waves of barbarians and vikings, the eastern empire continued Roman traditions and law for many centuries. The palace intrigue and back stabbing makes Game of Thrones seem tame by comparison.
A Short History of Byzantium is a condensed version of a broader three volume set.