During the period of time when dragons ruled over mortals, (c. Merethic Era), Miraak served as a dragon priest on the island of Solstheim. Discontent with his position, he sought out means to more power and more glory. He would come into the servitude of Hermaeus Mora, Daedric Prince of Knowledge and Fate. Under Mora's tutelage, he learned forbidden knowledge that turned him into the strongest of all of those who used the voice at the time. Miraak used this power and turned against his fellow Dragon Priests, and used his power as a Dragonborn to devour the souls of his slain compatriots.
During the Dragon War, ancient Nord heroes named Hakon One-Eye, Gormlaith Golden-Hilt, and Felldir the Old, had pleaded with Miraak to use his powers as Dragonborn to assist them in defeating Alduin, however, Miraak refused to do so and instead attempted his own rebellion against the Dragon Cult.
His rebellion was unsuccessful, though, and he was defeated by another Dragon Priest by the name of Vahlok who was made his jailor, restraining him to Solstheim. Before he could be imprisoned, however, Hermaeus Mora pulled him into Apocrypha. Vahlok was appointed as ruler of Solstheim and was made to swear an oath of vigilance to watch for Miraak's return.
Miraak remained trapped within Apocrypha until the 4th Era. He began to extend his power into Solstheim again and took control of the minds of the Dunmer people of the town of Raven Rock, the Nords of the Skaal village, and several native goblins of Solstheim to rebuild the temple on Solstheim and bring about his release from Apocrypha and the will of Hermaeus Mora.
The Last Dragonborn, pursued by Cultists of Miraak, journeyed to Solstheim to investigate why Cultists were claiming him to be a false Dragonborn and attempting to kill him. This trip to Solstheim eventually culminated in figuring out how Miraak was getting the power to influence the people of Solstheim and how to dispose of Miraak. In the end, Miraak was killed within the realm of Apocrypha and the people of Solstheim were released from his mind control.