This is a major tome, one that took awhile to finish. The easiest sections to read where the first two and the last, but this is not to say that the other sections where dry. I was especially shocked to be entertained by the Reformation sections (which usually strike me as rather dry). The book moves one through the major shifts in human thought: 1. the early church period (i. the founding of Christianity and the early persecutions/spread, and the odd marriage of political Rome and Christianity), 2. the Middle Ages (including the rise of feudalism, kings and monasticism as well as fractures between Catholicism and Eastern Orthodox; and the rise of Scholasticism), 3. The renaissance and reformation (Lutheran, Radical anabaptist, Calvanistic, and Catholic), 4. the Enlightenment (including Pietism, Romanticism, and Enlightenment), and, 5. Modern era after the World Wars.
It was very striking to me, as I read through this work, that religious violence is a very nuanced sort of thing: political leaders or kings may be Christian in name only, Christianity could be used politically (e.g. Kings, Rome), Atheist states and movements (e.g. French Revolution, rise of Socialism in China and Soviet Union, the fascists) killed millions, Christians hunted witches and engaged in crusades, etc. But one thin I don't think one can argue at the end of this book: the founder of Christianity, despite his hard sayings, lead a life worthy of emulation and peace, to the point of dying on a cross without defending himself; a founder that's hard sayings lead to the establishment of schools, hospitals, the concept of mercy and personhood in the pagan Rome. A great work.