So I happened to be reading this article:
It's about the wedding of a British duke that took place recently. Apparently, as well as being the Duke of Hamilton, he's also the Earl of Cambridge. But William (THE William) is Duke of Cambridge. This seems confusing to me.
Are the titles largely ceremonial these days, as opposed to having any tangible aspect to them? Just curious.
The oldest created titles would generally have been given with land - ie the powerful nobles would have had a good deal of actual territory to provide them with an income. That was a good few hundred years ago, though. I don't know whether the title and the geography were connected originally, but in any case the richest families no doubt acquired more land all over the place, by various means. You'll often find that these days the title doesn't seem to bear much relationship
to where the land *is*. For instance, the Duke of Devonshire's main family house is Chatsworth, which is in Derbyshire. The Duke of Norfolk owns a lot of land in Sussex. And you often see places with unexpected names in the 'wrong' towns, eg Norfolk Place (I think) in Sheffield (Yorkshire), which is part of the Duke of Norfolk's estates, and Bedford Square (in London), owned by the Duke of Bedford - ie the place is named after the peer rather than after the place. (We have a county of Norfolk and a town of Bedford.)
These are hereditary titles - you'll get the 16th Duke of Norfolk, 6th Duke of Westminster, etc. So the titles parade through our history, with different people owning them and the estates that go with them. Also, they generally manage to acquire subsidiary titles (and, probably, estates) as they go on, so the heir to the Dukedom will use a courtesy title that's one of his father's lesser titles, eg, the Duke of Bedford's heir is the Marquis of Tavistock.
Royal Dukes like Edinburgh and York and Cambridge don't get land to go with the title. York is the traditional dukedom given to the second son of the reigning monarch, and there are a handful of others that are used regularly. Anyway, you'll get Dukes of York, Clarence, Cambridge, Kent etc popping up throughout history because they were the monarch's sons [for instance, George III's sons: George, Prince of Wales (later George IV), Frederic, Duke of York, William (later William IV, I think he was Duke of Clarence), Edward, Duke of Kent, Ernest, Duke of Cumberland, Augustus, Duke of Sussex, Adolphus, Duke of Cambridge], but the title isn't inherited by the duke's son - that only happens when the dukedom is the other kind.
Prince Harry can't become Duke of York, though, at least not until his Uncle Andrew is dead, so that one will probably skip down to William's second son, assuming there is one. I don't know, but I'd assume there is probably a grant of income that goes with being a Royal Duke; whether it's paid by the monarch or by the state, I cannot guess.
I believe the rank of Duke is actually senior to Prince: I'm sure I read that a (legitimate) son of the monarch is born a prince, but raised to the rank of Duke.