Well, Eustace could be a prince I suppose because his cousins are kings and queens, although I'm not positive about that. But Digory, Polly, and Jill I think are more honorary royalty. They're lords and ladies but I don't remember what that really means. It's been awhile since I studied that sort of thing. I think the first quote is referring to what they all looked like to Tirian rather than what they actually are.

I think the first quote is referring to what they all looked like to Tirian rather than what they actually are.

I agree about that. Some of them are actual Kings and Queens, and the others are nobility - Lords and Ladies, and as such they would wear coronets (???) and diadems and such. At first glance, they all look so magnificent that Tirian doesn't notice the differences between them (which needn't have been very great anyway).

I think too that the narration referred to all of them as Kings and Queens because that is how they looked to Tirian. If you saw someone dressed magnificently and wearing a crown, you might think that they were royalty, too, and with good reason!

However, I think that everyone, when they get to Aslan's country, would be dressed in equal splendour regardless of their title. While Peter, Edmund, and Lucy are Kings and a Queen, they are dressed like Digory, Polly, Eustace, and Jill are dressed. So rather than all of them actually being kings and queens, they merely all look like them.

But Digory, Polly, and Jill I think are more honorary royalty.

They've done a lot for Narnia so perhaps they were made into Lords and Ladies kind of like being knighted?? I've read in places that nowadays you can buy a title. I haven't studied medievel times very much but I think that you can become a Lady or Lord without being royal but I'm not sure.

^^ but where would anyone buy a title in Narnia?

I don't think they were real royalty but since they were there at the creation of Narnia they are treated as such. Eustace and Jill also since they were Narnian heroes...

@Liberty: I don't think they actually "bought" the titles. I guess they are considered nobility because they were such integral parts of Narnian history--Digory and Polly were there at the beginning or Narnia; the Pevensies saved Narnia from the White Witch (and they're royalty anyway); Eustace and Jill saved Rilian and so they're heroes. I think they're just considered lords/ladies because they did so much and so they deserve it.
It would be funny, though, if people could buy titles--"how much do I have to pay to be Duke of the Lantern Waste?" "Oh, seven hundred [what is the Narnian currency, anyway?]"

As a side note, the currency of Narnia is in "Trees" and "Lions" both of which are coins, with unknown values.

The currency of Calormen is the crescent, which, according to C.S. Lewis, is roughly equivalent to 65 cents.

I digress.

I like to pretend that in Heaven, every girl is a princess and every boy is a king. Regardless of your status back on Earth or wherever you came from. So maybe C.S. Lewis had a similar idea or fantasy. Digory and Polly may have never been royalty or had any titles or exercised any political power. But once you get to the final destination, you are a princess or prince automatically and will live happily ever after.

Rather simple explanation, but to me it works

1 Peter 2:9 -"But you are a chosen people, a royal priesthood, a holy nation, a people belonging to God, that you may declare the praises of him who called you out of darkness into his wonderful light."

That was the only thing I think can explain it other than Tirian automatically assumed they were kings and queens.
Revelation 4 -10-11 "the twenty-four elders fall down before him who sits on the throne, and worship him who lives for ever and ever. They lay their crowns before the throne and say: You are worthy, our Lord and God, to receive glory and honor and power, for you created all things, and by your will they were created and have their being."