God's Battalions: The Case for the Crusades by Rodney Stark
My rating: 4 of 5 stars
The book's goal is to demonstrate why modern-thinking about the crusades needs to be significantly modified by the facts. Held up as the poster child for Christianity run amok, exemplifying the (typical, as it's believed) greed and war-mongering of Christians, the crusades in fact had very little to do with greed or even expansionism.
The crusaders responded to the Muslim incursions into the Holy Land, the abuse that pilgrims to the Holy Land were receiving at the hands of Muslims, and to Muslim desecration and destruction of sacred sites within the Holy Land. In other words, the knights of the crusades were not the instigators; they were provoked.
Further, the crusaders did not become wealthy in this venture; far from it. Rather, the crusades were expensive, and many knights invested fortunes and borrowed much in order to venture forth on what many of them believed was a sacred warfare on behalf of God.
The original plan was for the Europeans to fight alongside the Eastern Christians of the Byzantine Empire, and then, once the Holy Land was liberated from the Muslims, to return home, leaving the Holy Land back in Byzantine hands. But the Byzantine emperors, located in Constantinople, were not interested in Jerusalem; further, they often hampered the efforts of the European crusaders, even at one point siding with the Muslims against the crusaders. Thus did the crusaders, many of them, sacrifice by staying and overseeing the continued defense of the Holy Land. Such, however, was not their original intent.
Now the crusaders were not perfect, as Stark points out, but they get a bad wrap from modern day historians.
God's Battalions is an easy read. It gives a great picture of the Crusades, and it successfully demonstrates why they weren't near as bad as everyone says they were.