I'm reading this book: The Great Depression: A Diary: Benjamin Roth, James Ledbetter, Daniel B. Roth: Amazon.com: Books
It's in diary form with comments by the author's son. The author was a thoughtful man who lived out the Great Depression in Youngstown, Ohio. He was a lawyer who knew many people in the town. He comments on what happened to banks, real estate, stocks, etc. from 1931 to 1941. Lots of insights into what really happened to a prosperous part of the community.
I think it's worthwhile reading to consider if your investment approach would survive such a scenario
. Much worse then our present times. If you are an older investor you might have less time to see any recovery.
Here is a chart I've posted elsewhere that kind of goes along with the book's narrative:
BTW, I'm a nervous optimist with an AA of 65/35 stocks/bonds.