I really hope that at least most of the Brits doing this quiz got Roundheads. I was surprised to see that it was the least-known answer. I presume the English Civil War isn't taught outside of, well, England.
American Midsomer Murder fan here - I got it because of the episode about the reenactment of the Cavaliers vs. Roundheads battle and all the furor that it wasn't being done accurately.
I know of some Americans who learned about it in High School - the English Civil War (often called Wars of the Three Kingdoms in academia now, as it was not confined to just England) had consequences on the American colonies and eventually the US constitution.
My wife's favorite episode of Keeping Up Appearances is when they do the historical pageant about the English civil war, so that's how I first learned about the roundheads and cavaliers. :-)
John Radams and John Q Radams are offended that you forgot about them. Andrew Rohnson, Lyndon B Rohnson, George HW Rush, and George W Rush are also offended.
So far I've seen four comments suggesting alternative answers to the two presidents question without realizing that there's only one pair of name-sharing presidents where the last name starts with R. That says quite a bit about the quality of their attention to detail.
Please also accept Regina, Saskatchewan as the most important city in Western history. But, seriously, not a big fan of subjective superlatives like "most important". You could make a great case that Rome is that, but I think Regina - hometown of former NBA player Steve Nash - has something to say about that. I must have received upwards of 5 or 6 coupons for free tacos at Taco Bueno when he was Maverick and the team scored 100+ points. What has Rome ever done for us "... apart from the sanitation, the medicine, education, wine, public order, irrigation, roads, the fresh-water system, and public health".
I'll cast my vote for Regina because that was the first name of the nurse who delivered my second child when the doctor didn't make it to the hospital in time. I don't remember the name of the doctor but I'll never forget Regina as she saved my baby's life when she wasn't breathing.
The first African-American player in professional baseball was Moses Fleetwood Walker (thank you, The Dollop podcast). Many of the "rules" banning non-white players were created especially for him. Jackie Robinson had to tear them all down.
If my life depended on it and you asked me without context to tell you what the Reichstag was, I would have no idea, but I saw that clue and somehow it popped right into my head. Probably just scrolled through German terms starting with R, but it felt damn lucky.
The first African-American player in professional baseball was Moses Fleetwood Walker (thank you, The Dollop podcast). Many of the "rules" banning non-white players were created especially for him. Jackie Robinson had to tear them all down.
https://en.wikipedia.org/wiki/Moses_Fleetwood_Walker