
The story of how a group of warriors, driven by faith, greed and wanderlust, carved out new Christian-ruled states in the Middle East is one of the most extraordinary of all epics. The crusaders' stunning initial success started a sequence of great Crusades, each with its own story, that fundamentally shaped the Christian and Muslim worlds for two centuries, until the last Crusader castles were finally expunged. The energy and commitment that sent army after army into the eastern Mediterranean also led to the invasion and conversion of Central and Baltic Europe, Spain, Portugal, the destruction of the Cathars in Provence and the settlement of America. Told with great verve and authority, God's War is the definitive account of a fascinating but also horrifying story.'We are still living with the images and legends of the crusades...Tyerman tells us how the Church set about preaching the crusades, exploiting the perennial pessimism and guilt of the European nobility of the Middle Ages. He shows how crusading ideology penetrated the religious sensibility of the period, as well as its secular fiction and poetry...Of all the modern histories of the crusades it is the shrewdest, the most reliable and the most complete.' – The Spectator
Mostly Carroll Quigley's works like Tragedy and Hope, Anglo-American Establishment, or The Evolution of Civilizations.
Another I consider at the level of Quigley is Anthony Sutton.
There are quite a few less academically accurate books that are good eye openers anyway like Howard Zinn's A Peoples History of the United States. As a combat vet a couple that speak to the issue of war are God's War: A New History of the Crusades by Christopher Tyerman and The Shield of Achilles: War, Peace, and the Course of History by Philip Bobbitt (some really good stuff about the future of nation-states in a post nuclear world.)
Those are just a few key ones off the top of my head. Personally, what I find one of the best ways is to find a more narrow interest and find books written by or about the key players at the top. I often find that tidbits across various sources add up to very interesting insights.
Also, a must in my opinion for an American is the Norman Dodd interview about his investigations on the Reece Committee and how history was targeted as being needed to be controlled.
