In the books
In the A Song of Ice and Fire novels, Munkun is mentioned as the author of The Dance of the Dragons, A True Telling. It is noted that his work contains some inaccuracies, such as indicating that the dragon that killed Ser Byron Swann was Vhagar when in fact it was Syrax. Vhagar was ridden by Prince Aemond Targaryen, a brother and supporter of Aegon II Targaryen, and House Swann was among the supporters of Aegon II. Meanwhile, Syrax was ridden by Aegon II's rival, Rhaenyra Targaryen herself.
Munkun's work was said to be biased in favor of Rhaenyra, in contrast to the history written by Septon Eustace, which was biased in favor of Aegon II.
The World of Ice and Fire reveals that Munkun was a member of the council of seven Regents that ruled the Seven Kingdoms after the death of Aegon II Targaryen, as his successor, his nephew Aegon III Targaryen, was still a child. Munkun was the only member of the council that held office from 131 AC to 136 AC, when the council was dissolved. Munkun would also hold the office of Hand of the King.