It was WW1, and that book was even weirder than that: it was about Heinlein's direct author-insert character doing settler colonialism in space, grooming his adopted daughter, forcing cattle to inbreed to show what inbreeding does over multiple generations to preemptively discourage his kids (that he had with his adopted daughter) from banging each other, and making female clones of himself that he then groomed too. It fucking ends with him enlisting to fight in WW1 out of some incoherent blend of toxic masculinity and nationalism for a country he knows that he personally outlived, nearly dying, and being saved by his harem in a time traveling spaceship.
It was WW1, and that book was even weirder than that: it was about Heinlein's direct author-insert character doing settler colonialism in space, grooming his adopted daughter, forcing cattle to inbreed to show what inbreeding does over multiple generations to preemptively discourage his kids (that he had with his adopted daughter) from banging each other, and making female clones of himself that he then groomed too. It fucking ends with him enlisting to fight in WW1 out of some incoherent blend of toxic masculinity and nationalism for a country he knows that he personally outlived, nearly dying, and being saved by his harem in a time traveling spaceship.
Huh, my brain must have tried to delete that to save itself cause wow.