William Strauss, Neil Howe, 1992
I stumbled across this book one day when I was off-task (read: bored) at work. I had seen some boomers shitposting online about snowflake millennials, and wondered where the generational boundaries actually lay. This book turned up in search, so I started looking into it.
It's a tome of a book, and only concerns itself with American history, though you probably can see some similar themes and patterns applying to other regions like, mostly England, and probably the rest of Europe too.
At a high level, this book poses the idea that good times make a weak and disintegrated society, and bad times form a strong and cohesive society. That American history can almost neatly be divvy'd up between either a period of crisis or a period of spiritual awakening, and a period of intermission in between.
Strauss and Howe trace back through the entirety of American history to map out these rhythms. There's something to be said about how it wouldn't hold up to "academic scrutiny" or whatever, but it is still observational, and there is some insight and value to that. The generational biographies are fun to read, and give you a sense of how each generational peer group viewed society, their role in it, and how they responded.
It took me months to get through this one, but I really enjoyed it and it completely changed my perspective on American history, and even just the world we're living in today.
Strauss and Howe predicted a large secular crisis, on the scale of WWII or the American Revolution, to hit sometime in the 2020s. It's not hard to look around and kind of see the contours of that forming, and makes this all the more interesting of a read.