This is a book by the anthropologist Ruth Benedict. It's about the Japanese people. She wrote most of it during World War II, and all of it in the United States. She was working for the US government, which was at war with Japan at the time. Because of the war, a lot of people in the government wanted to know about Japan.
Ms. Benedict didn't go to Japan to do her research. This is understandable: It wasn't very easy to get there, and the people there might not have been coöperative anyway. Instead, she read everything she could find on the subject, and conducted interviews with as many Japanese prisoners of war as she could get her hands on. She intereviewed some Americans as well, both immigrants of Japanese origin and the children of immigrants. I guess that's not a really good way to do anthropology. I don't know enough about Japan to judge whether she got it right or not.
It appears that Ms. Benedict went through and revised the whole thing for publication after the war was over: Throughout, she speaks of the war in the past tense and makes references to MacArthur's occupation policies (she approves, by the way, and history seems to agree with both of them).
Ms. Benedict's thesis is that the Japanese work very hard and care very much about obligations and appearances, but that they have very little of what westerners would call "morality". She maps out the varying flavors and intensities of obligation (giri, gimu, on, etc. etc.) savored by the Japanese. She then goes on to explain (or try to explain) Japan's behavior in the 1930s and 1940s in those terms. There's some talk about "guilt cultures" (the West) and "shame cultures" (Japan). The idea is that people in guilt cultures do what they do because "it's right" (God's watching), while people in shame cultures do what they do because the neighbors may find out. This is obviously an oversimplification, at least as far as "guilt cultures" are concerned: Shame is universal. The degree of shame seems to vary a great deal from culture to culture, though.
The whole thing may be bullshit, for all I know, but it's a good read.