What a great book! Samurai William: the Englishman who opened the East by Giles Milton is all about the Englishman (William Adams) who was the real-life model for the main character in Clavell's Shogun.

Not only is it a very interesting subject (I had no idea that Europeans were so active in Japan so early) but Milton is a very readable author who knows how to combine hard core historical research with the kind of entertaining anecdotal history that makes it fun to read. I've had a long-standing interest in Japan, having spent a total of about 7 months there since highschool, and I've read a lot of early Japanese history, but most of those tend to overlook the European influence during that period. Milton has compiled a great deal of information about not only Adam's life in Japan, but what was going on with Europeans in the rest of Asia at the time. It ties in with his earlier work "Nathaniel's Nutmeg" (also a great read about the spice trade) in several places.

I also have a copy of Milton's "Big Chief Elizabeth" about the early English settlers of North America, but haven't had a chance to read it yet.