Link
As Link remained to stay in Hyrule after slaying Ganon, but one day a mysterious mark appeared on his 16th birthday. It was the mark of the Triforce and a piece glowing, the piece of Courage. After soon finding out the real legend behind the Triforce and of Hyrule, Link was destined to wake Zelda and retireve the Triforce of Courage in the Great Palace.
Zelda
The princess of Hyrule, Zelda, had a spell casted upon her to put her in a very deep sleep since she would not speak on the locatyion of the Triforce. Only the complete Triforce would wake her from her eternal slumber.
Impa
Zelda's nursemaid, Impa is the one that showed Link his destiny about the Triforce and gave him the six crystals and a scroll to ventrue the six palaces.
