... for a government under a Czar? Monarchy?

Like, if I wanted to talk about the Russian Revolution, is it correct to say "The monarchy was overthrown"? I know I could just say "the Czar" but I feel like there's a better word, right on the tip of my brain that I can't quite grasp.

That's a great question for which I had no answer but both dictionary.com and the OED online say it's a "tsardom". I never would have thought of that. Hope that helps or gives you another direction to look in

"Tsardom" (or "czardom") is correct, just like a "kingdom" is ruled by a king.

Oh I did think of 'czardom'! 'cause I was thinking, well 'kingdom' is a thing... but it didn't sound right at all to me (because you wouldn't say "The kingdom was overthrown"). But I guess if it's in the dictionary that's good enough for me.

I would use "Monarchy", as the term covers the area ruled over by a Monarch, and there are many meanings of Monarch, including King and Tsar.

Yeah, true. I thought there would be a better word, but I guess in this particular sentence 'monarchy' makes more sense than 'tsardom'

I'd have used the word 'empire', as the tsar rules over many nations and ethnic groups, stretching right across Asia and Europe. According to Wikipedia the Tsardom lasted until 1721, when it was superceded by the Empire of Peter the Great.

Personally I'd go for 'autocracy'. Assuming the Tsars had unlimited power, which I think they did.

Or you could possibly use 'reigning'

A Czar equals an Emperor (more or less), so I would choose the Empire.