Recently I have come to the phrase "to the Right of Attila the Hun" which allegedly describes the very conservative or reactionary person. Is it possible to construct similar phrases such as: "to the Left of Che Guevara", "to the Fanatic of Savonarola" or "to the Sex of Cassanova"?
Left or Right are a political spectrum, and there are degrees, so, "to the Left of Che Guevara," is a reasonable comparison.
"More fanatic than Savonarola," is sensible, but simply "fanatic" itself is not comparing anything. You'd need to use comparative adjectives in the sense you want.
"He's faster than a speeding bullet."
"She's brighter than Einstein."
"His humor is beneath slapstick."
"Right" and "left" are positions. Here they are being used metaphorically, but let's look at the literal meaning.
You can say "He is standing "to the right of" her" or "in front of" her, or "behind her". The phrase "to the right of" functions as a prepostion. To form a phrase like this you need a word indicating a position:
To the north of / To the side of / to the front of
"Sex" or "fanatic" aren't like that. So you can't say "to the sex of"
In this actual example "right" means politically right wing (ie "conservative" or "authoritarian", "captialist" or "monarchist" depending on which version of right wing you mean) and "left" means politically left wing ("progressive", "liberal" "socialist", "republican" again, there are different versions of the left)
So you can say "To the left of Che Guevara". But note that these expressions are hyperbolic. They are deliberate exaggerations for rhetorical or comic effect.
As others have pointed out, "to the right of" and "to the left of" refer to relative positions. It's meaningful to say that person A is "to the right of" person B, either in a literal sense -- they're standing next to each other and A is right of B -- or in a political sense -- A is more politically conservative than B.
This works because "right" and "left" denote relative positions. You can't say "to the fanatic of" because "fanatic" does not describe a relative position. A person can be a fanatic, of course. But if you want to describe a relative position, you would have to say "person A is more fanatical than B". Similarly, you could say "person A is more sex-crazed than person B".
Just a side note: The phrase "to the right of Attila the Hun" doesn't make a lot of literal sensse. The wording implies that Attilla the Hun was an extreme conservative. But was he? In the context of modern American politics, was Attila in favor of limiting government spending, defending the right to bear arms, opposing abortion, affirming free markets, etc? I don't know what Attila's positions were on any of those issues, or if he had positions on those issues. None of them are what Attila is remembered for. As a joke by a left-winger trying to compare a conservative to someone very out-of-date, maybe it works. But if I was engaging in serious political discussion, even trying to use exageration for humorous effect, I might say "to the right of Ronald Reagan" or "Margaret Thatcher" or "Adam Smith". Likewise I might say someone is "to the left of Karl Marx" or "Franklin Roosevelt".
And of course, if I was trying to be literal, I'd pick someone they really were left or right of.
I first encountered this phrase in the musical 'Evita' with lyrics by Tim Rice. I don't know if he was the first to use it. I can't find anything online about its origin. Rice later revised the scenario to make the narrator an everyman named Che, but in the original version, he was a fictionalised version of the historical Che Guevara.
I would add that Attila wasn't a politician, so was wasn't 'right' or 'left', but militaristic empires are usually seen as right-wing.
Lots and none at all. My daddy always said he stood "15 steps to the right of Genghis Khan", meaning exactly the same as your "to the Right of Attila…" except that the "15 steps" is stonger.
Either happens to describe a strong right-winger - by no means anything like your "… conservative or reactionary person…" though that matters not at all.
What matters is the process of comparison, not the content of the things being compared.
As with "… to the Left of Che Guevara", the phrase is a simple comparison… "… more than Attila…" or "… more than Che…". Please note, there can be no question of one being more or the other less because they happen to be left-and-right "opposites". The phrases are purely about strength or quantity, not subject or quality.
Quite separately, neither "to the Fanatic of Savonarola" or "to the Sex of Cassanova" could ever work, nor even be comparable.
For those ideas, you would first drop the capitals and then use "… the fanaticism of Savonarola" or "… the sexiness of Cassanova".
Do the differences between "fanatic" and "fanaticism" or "sex" and "sexiness" make sense to you?
The asker seems to understand what right-wing means. The question is about the difference between "far to the right" and "to the right of Attila the Hun". What to we gain by adding a famous historical figure?
It's humor. Instead of saying "Something is X" you say "something is more X than Y", where Y is something unexpected and funny-sounding. "To the left of Che" is only a little funny (he wasn't a politician). "To the left of Robin Hood" is better, since he's not real. But "to the left of Santa Clause" is the best -- red suit, free stuff, magic reindeer -- that's funny. In the original, we could have used Genghis Khan, but Attila the Hun sounds funnier. Mussolini might have worked (funny-sounding and only one word).
We changed "more right-wing than" into "to the right of" because good humor makes you work a little to figure it out: it's not positionally to the right -- there's an extra step to know it's about politics. Then we bring up a slavering warlord who swept through Europe to attack Rome. What? That's unexpected and funny since it's so extreme. Plus we have to know that right-wing politics is traditionally pro-military (without that, its not funny at all. "To the right of Ted Bundy" isn't a joke).
Part of why "more X than Y" works is that you don't need to understand Y. It's obvious what "hotter than Jayne Mansfield covered in Vegemite" means, even if you've never heard of either. As a bonus, I've implied she's nude (clever word-play is funny) and that I've got some sort of fetish (those are always funny, if subtle).
Similar phrases might be "older than dirt" (?? dirt doesn't have an age. But with some decoding it means "older than the planet"). "Sexier than a Trans-Am full of drugs" (an unexpected funny image, conjuring a Wild Party eventually leading to sexy people). "Uglier than parallel parking your mom's station wagon" (uses an alternate meaning of ugly, and paints a humorous picture of a 1980's teen-ager learning to drive). For fanatic, maybe "more fanatic than your kid's first time at a waterpark" (that's not funny, yet, but "Mommy -- watch me!" isn't the fanaticism we were expecting).