"The Worldwar series is the fan name given to a series of eight alternate history science fiction novels by Harry Turtledove. Its premise is an alien invasion of Earth during World War II, and includes Turtledove's Worldwar tetralogy, as well as the Colonization trilogy, and the novel Homeward Bound. The series' time span ranges from 1942 to 2031." Now I haven't read them all and the reason why is that I found them not that enjoyable to read. It's not the subject matter per se but more of the writing style but I did get through the first 4 books and just didn't have any need to finish it. But, if your looking for aliens, alt-history and all sorts of other WEIRD shit, then this series might be for you.