Samurai William by Giles Milton.
Best book I have read for a while. After visiting Hirado a couple of months ago I wanted to learn more about Adams, the English trade factory and why it failed. Giles Milton did a lot of great research to write this. He notes all his sources in the back which is primarily diaries, log books and letters from the English, Dutch and Portuguese.
Although the book is centered around William Adams it isn’t primarily focused on him. Milton adds a lot of material dealing with events of the time as well. The last two chapters were very frantic and emotional.
If you wanna learn about life in Japan around the famous Sengoku Jidai, beginning of the Edo period, Dutch, English trade, Portuguese influence, Jesuits, and of course Adams becoming a samurai and direct retainer of Ieyasu Tokugawa, this is a great book.