I didn’t know that his wife had a half-sister
Yes, Sally Hemings was originally the slave (and daughter via slave rape) of Jefferson’s father-in-law. She was then transferred to Jefferson.
The more you learn about Jefferson/Hemings, the more ick.
The Churchill bit makes a good trivia question. “Which WWII leader’s diary featured long diatribes about Jewish conspiracies?” Very few will guess Churchill, but there it is.
I wouldn’t be surprised if Hitler’s diary also contained such. You said WWII leader, and did not indicate a side.