Barbara Tuchman, absolutely; particularly The Guns of August and A Distant Mirror: The Calamitous Fourteenth Century (The Black Death, the Hundred Year's War, the Crusades).

>Justin? Foote, also on the Late Unpleasantness.
would that be Shelby Foote's The Civil War? if you're at all interested in the CW, this is the ne plus ultra; the Ken Burn's PBS series was marjorly influenced by this.