Character Analysis
A Fearful King
Like many of the characters in this book, Vortigern is the stuff of legends. If you check out Geoffrey of Monmouth's pseudo-historical History of the Kings of Britain, you'll find the Big V there, terrorizing all of Britain with his Saxon allies.
But in The Crystal Cave, Vortigern is nothing more than a man backed into a corner by some seriously bad life decisions. Merlin sums it up like this:
He was a hard man, as one must be who had taken his throne by murder and held it with blood; but he was a strong king in a time when there was need for strength, and it was not altogether his fault that his stratagem of calling in the Saxons as mercenaries to help him had twisted in his hand like an edged sword slipping, and cut to the bone. (I.9.2)
Merlin's being nice when he says "it was not altogether his fault" that the Saxons went berserk and started terrorizing his land. Vortigern is not a rightful king—he's taken the throne through regicide (that's what it's called when you kill a king)—and has invited enemies into his borders.
But it hardly matters who's to blame at this point. Young Merlin sees that Vortigern is no longer ruling the kingdom. He's fighting for his life: "It did not need the makeshift hall, the court which was less a court than a gathering of fighting chiefs and such women as they kept by them, to indicate that this was a man on the run. Or rather, a man in a corner. But a cornered wolf is more dangerous than a free one, and Vortigern was still a wolf" (III.7.1).
Yeah. Vortigern's a desperate man who's about to take some very desperate measures.
Faulty Tower
Vortigern is a throne-grabber. He murdered Ambrosius and Uther's older brother, Constantius, instead of supporting him as he should have. Now he knows that the righteous hand of karma is about to slap him upside the head. In order to forestall that, he decides to build a huge tower in Segontium so that he can lock himself in and hide.
But the tower walls keep falling down.
Now, Vortigern is one superstitious dude. It would never occur to him to, say, hire an engineer to figure out the problem. Instead, he asks his priests to come up with a plausible solution. What they "learn" from their soothsaying is that Vortigern needs the blood of a lad with no human father to mix into the cement of the tower.
Vortigern thinks he's hit the jackpot with Merlin because rumor has it that Merlin's daddy is a demon. Eyeroll. When Merlin appears before Vortigern, he can see that the fear factor has gone through the roof: "There was sweat on his face, and I saw his hands twitch on the arms of the chair. The man was humming like a harp-string. The tension ran right through the hall, almost visibly. I felt my skin prickle, and a cold wolfspaw of fear walked up my spine" (III.7.44).
Vortigern has been reduced from a mighty king to a paranoid scaredy cat who resorts to looking for wonders and signs to save him. And Merlin is perfectly happy to put on a show for him, especially since it will give Ambrosius a chance to come at this bad boy once and for all.
A Fitting End
You might be tempted to feel sorry for Vortigern, especially after you find out how he meets his end. But seriously, we're not shedding too many tears. We learn one additional detail about his final stand that says a lot about his character:
[Ambrosius] sent a man to Vortigern with conditions for surrender. Vortigern, who must have seen the defection of some of the British troops, and who well understood Ambrosius' position, laughed, and sent back the messenger without a message, but with the man's own two hands severed, and bound in a bloody cloth at his waist. (V.1.20)
The upshot? Vortigern is not a just king. He may not even be a sane king by the time Ambrosius has returned. If the "Arc of the moral universe is long, but bends towards justice" (thank you, Martin Luther King, Jr.), then it's clear that the coming of Ambrosius is the final, fatal sign for Vortigern.
Vortigern's Timeline