GoT: How Long Has Jorah Been Doing That? -- Vulture

The Mother of Dragons might be surprised to learn that her "most trusted advisor, most valued general, and dearest friend" Ser Jorah Mormont, who has been at her side since her wedding day, was actually once a spy for the men ruling Westeros, the kingdom she wishes to conquer. But to viewers paying close attention, this is no surprise, as characters on the show have discussed it many times. The only question is, when did he stop spying? When did his betrayal turn to love?

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GoT: How Long Has Jorah Been Doing That? -- Vulture: