Years of Rice and Salt
by Kim Stanely Robinson. I never read Sci-fi, but this one is really good. He reimagines the world in a scenario in which the Plague killed off 99% of Europe rather than just 1/3, leaving Europe empty and the Chinese to become the homogenous world power. Islam, rather than Christianity is the dominant world religion. He holds it together by having the same group of characters reincarnated throughout the different eras the book covers, meeting in the Bardo after each life to discuss their successes and failures to end the cycle of birth and death. It's really fascinating reading.