I've always been interested in Romance of the Three Kingdoms games, but I really have no idea what they're like. I read they're similar to a Civilization game. Any truth to that?
No, they are not quite like civilization. More like the Paradox series, as I understand it. Koei has carved out a unique niche that dates from the mid 80s. Games on the NES were Nobanoga's Ambition, Romance of the Three Kingdoms II, and Bandit Kings of Ancient China.
Basic gameplay is this: You build up your empire on a map, choosing what a province does during a particular turn (train army, farm, flood control, move troops, marry off daughters, attack, etc...). There are random weather events, the Yellow river floods, and you get stomped by the AI if you show the slightest weakness. Get too strong, however, and your enemies will unite against you. Then you fight.
The fight scenes are (were) carried out in a 2d hex-like representation of a map. In most games, you only had a troop number and a flag. Took me a while to figure out in NobAmb that that troop number corresponded to either samurai, cavalry, ashigaru tanegashima (matchlock rifles) or ashigaru spearman. Romance was bit unique in that you also saw a general's name. Sometimes you could turn the general to your side. I seem to recall Lu Bu was a knucklehead about this. He was certainly a "What have you done for me lately type general". But too powerful to let the computer have him.
Anyway, that's what I recall. This looks way more complex than even Rt3K3 (SNES), so your enjoyment may vary.