Claudus/Claudius was the lord of the thundercats in the OS.
The original series is kind of weird because Jaga also at one times used the Sword of Omens. It was kind of inconsistent or unclear how the lineage worked in that series.
EDIT: We had a thread about it a while ago, in which I prove myself unable to spell at all: http://www.thundercatslair.org/forums/showthread.php?t=6461
Claudus/Claudius was the Lord/King/Ruler of the Thundercats. Jaga was the Guardian of the Sword of Omens, he also was Claudus Succesor for the time being before it was Lion-O’s turn to rule.
I think it would be awesome if despite being King of thunderra, he still has to prove himself to be a true lord of the Thundercats (annointment trials) when he comes of age or something. In the premiere didn’t Jaga say something like “only the sword of omens can tell us if u truely will be a lord of the thundercats”??
I like the idea, the thing is Lord and King have different duties. As kings now and then the king DID decide much but did not do everything right? He had other man do the dirty work (not always but you know what i mean) while he did his stuff.
Same goes for the king here in Sweden, though our one does not decide much he is more like the “Lord” as he just does his kind of work.
What ever the 2011 Lion-O is King or lord or maybe both is not important really what we know is that he is the ruler and he has to prove himself.
The guys making the show have already said Lion-O will have his anointment trials. They said it would only be about 2 episodes long instead of 5 though.
Does that mean it will be a one-hour special, like the premiere was? 
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He certainly did. It went something like, “I am Lion-O, Lord of the ThunderCats, and I demand that you release us!”
I like this idea.
There is still THAT problem i posted about, besides i think in this series king and lord are probably the same thing.
I always felt that in TOS and this series that Lord and King were basically interchangeable.
I actually never liked any of them, and always felt that title (Lord) a little… denigrant? It always sounded to meas “Master”, like saying that he owes the other TCs and they had to do their will no matter what (which they did btw, it was common in the OS to hear “Lion-o is the Lord of the TCs, and if he had decided it that way, we should do it”).
I’d rather have used the word “leader” or something like that.
Lord is a cooler word than leader.
Lord is a title for nobility. It doesn’t mean his subjects are his slaves and it doesn’t mean he owns them if they show him the respect of calling him by his title. If someone had called Cheetara “Lady Cheetara” would you think the same thing? because it’s basically the same title with a different gender.
Never thought of "lady"as the female word for “lord”.. you got a point then.
I know it wasn’t the intention of the show to portrait it that way (the lord thing), but I got that impression from time to time, especially when, as I said, one of the TCs complained about something Lion-o said, and another TC argued “he’s the Lord and had decided that, so we have to do that”. Pretty authoritary IMO.
I might be reading in too far though 
No your not actually. Lion-O is the defacto king of Thundera in both series. He would listen to the other TCs certainly but he was/is the leader in both series.
Well Lion-O is the king. It’s not a democracy. Of course they do what he says. He might listen to their council, but ultimately decisions are up to him.
Military Democracy
There a saying that the military is a perfect democracy… Until it isn’t. Meaning, anyone is allowed to have his/her input, suggestions, put forth ideas. But once an ideas is decided by superiors, that’s the way it is. I kinda look at it like that. He’s Lord. What he says goes. But, he has to be a wise ruler, and listen to his counsel and advisers.
Dictatorship omg!!! (nat)
Thing is though, there are “certain levels” of Dictatorship, i mean in the middle ages when kings were the big bosses and decided everything. There you had dictators. Only big one now i think is North Korea?
No it’s a Monarchy.
I mean the way it’s ruled.