The Modern Mind: An Intellectual History of the 20th Century by Peter Watson
A more than serviceable guide to the major cultural theories and movements of the twentieth century. I did notice a few errors, though, and I'm not even a professional historian. A more serious complaint I have is that Watson, in the early chapters of the book, does not allude to the reappearance of themes later in the book. So, for example, you could read the first quarter of the book and learn about Freud and psychoanalytic tradition. But if you stopped reading there, you'd have no hint that in the last quarter of the book Watson covers the major debunking of Freud that happened later in the century. While Watson adequately justifies the focus he places on the Western tradition, I was deeply disappointed that Mahatma Gandhi received all of one sentence.