From the Harvard University Press Blog:
Capital in the Twenty-First Century was an unusually ambitious book. What prompted you to write another major book so soon?
I’ve learned a lot since the release of Capital in the Twenty-First Century. I was invited to countries about which I knew little, met new researchers, and participated in hundreds of debates. All these exchanges pushed me to renew my reflections. To summarize Capital briefly, it showed how, in the twentieth century, the two world wars led to a very strong reduction in the inequalities inherited from the nineteenth century. I also pointed to the disturbing ascent of inequalities since the 1980s. But the book had two main limitations. The first is that it was very Western centered. In this new book, I widen my scope: I examine the history of “ternary societies” [organized into three classes: nobility, clergy, and workers] and societies of owners or proprietors, but I also study slavery societies, colonial regimes, communism, post-communism, social democracy, the case of castes in India, and inequality regimes in Brazil, China, and Russia. The second limitation is that Capital only scratched the surface of the deep question of the ideologies that support inequalities. It was a black box that I decided to open.
More here.