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Yi Gae (1417–1456) was a scholar-official of the Joseon Dynasty and one of the six martyred ministers. He was born to a yangban family of the Hansan Yi lineage, and was the great-grandson of Goryeo period philosopher Yi Saek.
Yi passed the higher examination in 1436, and he was appointed to the Hall of Worthies by Sejong in 1441. After Munjong rose to the throne in 1450, he was appointed to provide personal instruction in the classics to the prince, who became the young King Danjong in 1453.
In 1455, Danjong was overthrown by Sejo. Yi joined a conspiracy of other high officials to overthrow Sejo and return Danjong to the throne; but just before the plot would have unfolded, it was betrayed to the king by Kim Jil. Arrested, he refused to repent under torture and was executed.
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