Maester Aemon

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Maester Aemon was the maester at Castle Black and one of Lord Commander Jeor Mormont's closest advisers in the Night's Watch.

He was born Aemon Targaryen and was the last known Targaryen in Westeros. He was the great-uncle of Daenerys Targaryen, and unknown to him, was the great-great uncle of Jon Snow. Aemon's origins have long been forgotten by most, as he remained dedicated to his vows as a Maester and a brother of the Night's Watch for many decades.

He is played by Peter Vaughan.