Vilgefortz of Roggeven was, at varying points, a Druid, a Mercenary, a Mage, and eventually, the greatest living sorcerer. His story is long, vague, and convoluted. Most of what we know of the man is said by himself, and he is not a very modest gentleman. The following synopsis is told using information gathered from the Witcher book series, and will thus contain spoilers. Depending on the route taken by the show, this will contain spoilers for that as well.
Sodden and Treachery
Vilgefortz’ first political movement was at Sodden Hill. After properly showing his badassery at Sodden, he was a major portion of the peace talks.
“The wizards won’t back an assault on the left bank,” confirmed Vizimir. “The peace agreement was the work of Vilgefortz of Roggeveen. It is well known that his plan was for the armistice to gradually turn into permanent peace. Vilgefortz will not back a war. And the Chapter, believe me, will do whatever Vilgefortz wishes. After Sodden he has become the most important person in the Chapter—let other magicians say what they will, Vilgefortz plays first fiddle there.”(Page 221 of Blood of Elves)
King Vizimir is, however, wrong. Vilgefortz fought against the Nilfgaardians, but it is clear that he did not fight for the North. His supposed goal was that of peace. He wanted things to go back to the status quo. If he was actually fighting for the North, Sodden Hill could be used as a turning point. Nilfgaard crushed, the North properly rallied with the Mages behind them, Nilfgaard could’ve been conquered as far south as Nazair. But that’s not what Vilgefortz wanted.
If all the lands to Nazair were taken, Emhyr would be fucked. His throne is dependant on his overwhelming power. He is only Imperator because men fear him. The second there is even a whiff of weakness, he’d be devoured.
We don’t know when Vilgefortz started working with Emhyr, but I imagine it started shortly before the Northern War peace talks. That would explain why he gave favorable terms to Nilfgaard, and also to Temeria. We’ll get back to why this, but we’re not there right now.
Vilgefortz and Emhyr had a simple plan on Thanedd. A growing block of Mages are more loyal to their kings than they are to magic. Nilfgaard is terrified of another Sodden, so Emhyr planned to take them out. Vilgefortz, being the strongest living mage, was supposedly on Nilfgaard’s side. So I’m going to take a break about Thanedd.
‘The Imperator is certain he was betrayed on Thanedd. The traitor is Vilgefortz of Roggeveen, a sorcerer, and his assistant Rience.
He has two, Rience and Schirru. Rience is probably the most well-known one, and he’s kind of a piece of shit. Rience is honestly a god awful spy. He’s a drop out from Ban Ard, the male magic school. He joined the Kaedwenni Secret Service but holds not loyalty to Kaedwen. In fact, when Vilgefortz paid off all of Rience’s debt, he jumped sides to Vilgefortz. I’m going to be honest, I have no idea why Vilgefortz bothers with Rience.
The strange, elusive Master Rience. The insolent, self-assured Master Rience who does not even bother to use aliases or false names. Master Rience who, from a mile off, smells of Nilfgaardian chimney smoke. And of being a renegade sorcerer.(Page 198 of Blood of Elves).
Seriously, what sort of assassin doesn’t use fake names? Later in the Tower of Swallows, Rience is captured by a ragtag group of sellswords and low psionics. Want to know how? A bucket of milk was thrown on his invisible form, then a bucket of flour, and finally, bonked on the head with a frying pan. Oh, and than Ciri cuts his fingers off with ice skates.
We know less about Shirru. He’s a half-elf with weirdly yellow skin, but other than that… we don’t really know much about him. He’s a sadist, who gets joy from killing Geralt’s crippled friend, Fenn. His goal is to kill Geralt, so he hires the Nightingale and his gang to do it for them. That falls apart when Terrorists/Freedom Fighters kill the gang, and as he runs away from Geralt, he gets captured by druids and toasted.
Another is Leo Bonhart, but he deserves his own paper to be honest.
Thanedd and Beyond
Rience was to enter Thanedd from below. With him were a Scoia’tael commando, a group of elven terrorists with Isengrim Faoitiarna, and Cahir Mawr Dyffryn aep Ceallach. The goal of the event was simple: Capture Ciri and return her to Nilfgaard. Secondary objectives include the murder of as many mages as possible.
The problem occurred because Vilgefortz had his own objective: Capture Ciri but instead of taking her to Nilfgaard, he plans to kidnap her for his own ends. This is where the Nilfgaard connection is important: Stygga Castle is Vilgefortz main base, and it is in Nilfgaard.
After Thanedd, Vilgefortz vanishes. He’s gone. The Lodge, the North and even Nilfgaard try searching for him but none of them can. He vanishes.
Emhyr thinks he has Ciri, but no one knows where he is.
‘And don’t try to pull the wool over our eyes, Vilgefortz. You’re using Rience and his casket not because of the amount of work you have, but from fear of the army of sorcerers, your former comrades in the Chapter, who are scanning the whole world in search of traces of magic with your algorithm. Were you to try teleportation, they would locate you in an instant.’(Page 374 of The Tower of Swallows)
That’s why he uses Rience. He is terrified. Because Vilgefortz is awful at politics. He masterly set up a conflict between Nilfgaard and the North, aided the revolutionaries against Nilfgaard and helped organize the other northerners with resentment against Temeria.
But all of his power was reliant on being useful to Nilfgaard.
He spends all of the post-Thanedd plot working to cover his tracks. Rience has shit the bed and drowned in a lake. Shirru has been torched. So he has to make friends with questionable cutthroats. Stefan Skellen, a traitor to Nilfgaard, former Lord Coroner and a constitutional monarchist, and Leo Bonhart, the sociopathic murderer. Vilgefortz betrayed his friends and he ruined himself in the process.
He’s a spider in his web on the porch of the mighty. He caught wasps for Emhyr, and proved himself of use. But the second he bit Emhyr’s hand, he was squished. Vilgefortz is a powerful mage and misunderstood that to mean he was a powerful political player. And he managed to isolate himself from everyone who could’ve helped him. Nilfgaard, the North and Lodge all want him dead, and he can’t stop all of them.