To the best of my recollection, this is the first book on medieval history I have read. Consequently, there was much for me to learn. The book wasn't quite what I expected; it's more of a lengthy historiographical essay than a recitation of historical events and figures. Thus occasionally the time frame gets a little confusing, since he is crafting his book around themes rather than strictly recounting events in chronological order. Nevertheless, he does proceed from the second century to the fifteenth.
Cantor did an excellent job of outlining the differences between the early, middle, and later middle ages. Along with that he stressed certain themes, two in particular: the emergence of a distinctive western European civilization, and the always prominent and impactful interactions between church and state, church in this case being the Roman Catholic Church alone.
It should be noted that this history is entirely Eurocentric. The Mediterranean world enters in only as it interacts with and impacts Europe. Africa and Asia are barely mentioned. For example, there is only one brief mention of the Mongols, despite the fact that Genghis Khan and his sons conquered more than twice as much territory as any other person in history, conquered the most densely populated civilizations of the thirteenth century, and connected Europe and China through trade and diplomatic contacts.
Cantor goes into depth discussing various theological and ecclesiastical developments throughout the period, and illustrates how Aristotle and Plato continued to have great influence on both church and state. I was impressed with how well he understood the sometimes complicated theological debates, and how they affected the laity as well as the clergy.
If you are interested in medieval history, this would not be a bad book with which to start.