Castle Ironfist is a castle in Might and Magic VI: The Mandate of Heaven, and is located in the town of Ironfist in the Castle Ironfist region. It is the location of Nicolai Ironfist, heir to the throne, and the regent Wilbur Humphrey.
The party must talk to Wilbur Humprey to end the Bring Sulman's letter to Regent Wilbur Humphrey at Castle Ironfist quest. To earn his vote on the High Council of Enroth, the party must complete the Find Lord Kilburn's Shield quest.
When the party has secured all the votes on the council, they must complete the Find a cure for Slicker Silvertongue quest to convince Humprey's representative Slicker Silvertongue to vote for them. The party manage to uncover proof of Silvertongue's ties to the Temple of Baa, and Humprey gives them the Bring the the letter detailing Silvertongue's treason to the High Council in Free Haven quest.
Humprey can also promote paladins in the party to crusaders if they complete the Rescue a Damsel in Distress quest, and promote crusaders to heroes if they then complete the Slay Longfang Witherhide quest.
Nicolai Ironfist will disappear after the party has spoken to him, starting the Find and return the Prince quest. When the party is trying to cure Archibald Ironfist, Nicolai will give them the Find the Third Eye quest.
The back entrance to the castle lets the party acccess the roof. Here, they can find Walter Hargreaves, who teaches expert diplomacy; Elton Astrogate, who teaches expert learning; and Elton's son Kim. This is also the location of the King's Library.