On some occasions, Terry Pratchett, wondrous author of the Discworld books, has spoken about Lord Vetinari. Those moments, along with links to the full interviews, are reprinted below.
Q: And the longstanding objections to moveable type?
As Lord Vetinari says, "History is a bit like earthquakes. The strain builds up and builds up, and then overnight a whole field of turnips has moved six feet along the fault line." From a practical standpoint, the moveable type is used by the Dwarves. Politically, it would not be a good idea to fall out with the Dwarves, just at the moment. There are a lot of little reasons why it is in everyone's best interest to allow this to happen. Lord Vetinari's main objection to moveable type is that it makes it much easier for a lot of people to actually know what's happening. But he realizes that if you own the newspapers, then you can prevent large numbers of people from knowing what's really happening.--Writers Write: The Internet Writing Journal
"On the other hand, a gag that no-one's ever said they've got is the Patrician's name, Lord Vetinari. I always think of the Patrician as a vaguely Florentine prince, a sort of Machiavelli and Robespierre rolled into one. And of course there was Medici. So I thought if you had the Medici then you would have the Dentistri and the Vetinari. The Discworld is full of things which don't look like gags but are gags if only you can work out what the intervening step is which I haven't given.
Amazon.co.uk: Was it difficult to wave away the Discworld wizards' established rule against movable-type printing?...
Pratchett: No. I'd been laying the groundwork for some time. Omnia and the Agatean Empire have printing, the dwarfs are now a politically-powerful group and Lord Vetinari is getting to grips with the information age. Things happen in Ankh-Morpork when it's in the interest of the majority of powerful groupings to let them happen. Besides, Vetinari would be the first to see that newspapers could have a very useful part to play in the Byzantine politics of the city.
Pratchett: It becomes pretty clear that William takes after his totally arrogant father Lord de Worde, even though he's so sure he doesn't! Yes, characters generally seem nicer from inside. Is this why you so rarely use Lord Vetinari's viewpoint--to keep him distanced and menacing?...
Pratchett: Exactly. You never quite know what he's thinking on the next level down.
Amazon.co.uk: And about time to finish. Dare you comment on Terry Pratchett: Guilty of Literature, the Science Fiction Foundation's new collection of academic essays about your writing?
Pratchett: It was very ... kind of them. If I'd known anyone would take that much interest, I'd have written better books.
When some people on alt.fan.pratchett questioned whether Vetinari would really be the type of man to throw the kind of party described in _Mort_, Terry answered:
"I've always thought the Patrician is a party animal. Can you imagine waking up next day and remembering all those witty things you said and did, and then realising that he was listening?"...
During one of those interminable "which actor should play which Discworld character if there was a movie?" discussions, Terry gave some insight in how he himself visualises the Patrician:
"I can't remember the guy's name, but I've always pictured the Patrician as looking like the father in _Beetlejuice_ -- the man also played the Emperor of Austria in _Amadeus_. And maybe slightly like the head bad guy in _Die Hard_."
The actors Terry is thinking of are Jeffrey Jones and Alan Rickman, respectively.
In any event, the Discworld has changed over time as Pratchett honed his skills as a writer. In early books, Pratchett referred to several characters only by their title. The Archchancellor of Unseen University orthe Patrician of Ankh-Morpork. As time progressed, the characters acquired names and more definable personalities.
"In those days, the Archchancellor would change at least once per book. I'm a little uncertain about [whether the Patrician changed or has always been Lord Vetinari]. Sourcery actually marked the boundary line. The books before that were 'Old Discworld'; the books after that were 'New Discworld." They are the same place, but written by a better writer.
"Because the early ones were written in the fantasy tradition. You populate,apart from your heroes, with rogues, beggars, vagabonds, lords, whores... you don't think of them as characters. But I find it much more fun to bring them forward as characters."