You've got one of my all-time favorite non-fiction writers: Barbara Tuchman. You might be interested in the works of two others: Elaine Pagels and the late Stephen Jay Gould. Pagels wrote several books about the Gnostic Gospels. Stephen Jay Gould wrote mostly about natural history. Both writers combine a first-rate scholar's understanding of the subject with a gift for writing readable prose.

ETA: I also (tentatively) recommend Why We Eat What We Eat: How Columbus Changed the Way the World Eats by Raymond Sokolov. I haven't read the book, but I've read many of Sokolov's columns for Natural History Magazine, and they were excellent.