The Wolf Queen Awakened

Walkthrough
A courier finds the Dragonborn and advises them to seek out Falk Firebeard in Solitude.

As it turns out the summoning of Queen Potema the Dragonborn stopped during The Man Who Cried Wolf actually let her escape as an ethereal being, causing serious further problems in the world.

Speak to Styrr
Falk Firebeard therefore suggests following the advice provided by Styrr, a priest of Arkay, who lives in the Hall of the Dead in Solitude. He will give the player Turn Undead and Potema's Catacombs Key. The latter key unlocks the metal gate in the Temple of the Divines cellar, leading to Potema's Catacombs.

Defeat Potema
Make your way through the catacombs, to enter the Refuge to finally face off with Queen Potema in the Sanctum. Resistance in this final showdown will be significant, with powerful draugrs (×7) attacking. With the Dawnguard DLC, there will also be some vampires of varying strengths.

Retrieve Potema's remains
Once the draugrs have been defeated, Potema's Remains, a ghost, will directly confront the Dragonborn. Kill her to then pick up Potema's Skull on her throne. Continue on to the Secluded Chamber that leads to a balcony overlooking The Dainty Sload. Instead of backtracking, simply quick travel to Styrr.

Give Potema's remains to Styrr
Styrr will sanctify Potema's Skull, and thank the Dragonborn for his deed.

Return to Falk Firebeard
Then visit the Blue Palace and tell Falk Firebeard that all has been resolved. He will reward the Dragonborn with the Shield of Solitude, and see him as Defender of Solitude. And there is also some gold.

Die Rückkehr der Wolfskönigin