William Leonard Langer was an historian specializing in the diplomacy of the late 19th and early 20th centuries. A graduate of Harvard University, he taught at Clark University before accepting an appointment at Harvard University, where he eventually served as the chairman of the history department. He was on leave during World War II as head of the Research and Analysis Branch of the Office of Strategic Services, and served as president of the American Historical Association in 1957.
Interesting, but clearly written for a more academic, researching audience, rather than a casual reader. It's very dense and covers a large number of events and people over a very wide area, thus making it quite difficult to ingest and understand of the information within. Reading it over a long period of time didn't help either. That being said, it was certainly an interesting book I found, at times, hard to put down, especially when covering some of the more crucial moments from the period. I certainly learned a lot about the period, and I'm sure the book will come in useful as reference in the future, if I need to know anything about the political and social situation in the 1830s and 40s.