Breezy overview for those casually interested in Eastern Roman Empire. Quick guide over rulers and important events such as The Great Schism, Justinian Plague, up to the Siege of Constantinople.
The writer tells the story with flair, which in turn makes certain parts of it memorable. (Especially last two chapters nearing the fall of the capital)
May be just me, but the presentation is oddly remindful of classics public domain work by e.g. Livy. There is long list of kings, some slap-dash explanation of intrigue, and when it comes to siege and warfare, a bit of dramatic effects sprinkled.
Short and easily read, but note that it covers such a time span -- 1123 years -- that many things are bound to be glossed over.