Ignoring technology, and just looking at some big events:
WW1 was one generation away from WW2.
The American civil war was roughly 2 generations from WW1.
The Napoleonic wars were roughly 2 generations before that.
The American Insurrection was roughly 1 generation before that.
I've ignored the Cultural Revolution, Spanish Inquisition, Russian Revolution and my own particular favourite - the invention of bebop, but you could put those in as necessary.
I remain unconvinced by Smokin' Joe's timeline.
I do know one thing that hasn't changed. People telling me since I left school that I'll soon have more leisure time. I'm fully expecting that rug to be pulled from under me once again in a few years as I hit retirement age.