Board Thread:Lore Discussion/@comment-5277094-20140605150759/@comment-16047389-20140728214043

Akatosh would not have wanted the Dragon Priests to exist at all. He was against the Dragons ruling over Man, and did not like Alduin's abuse of power. That's why the Dragonborn was created.

In fact, Miraak was probably intended to put an end to the Dragon Cult and slay Alduin. But Hermaeus Mora got to him first, and fed Miraak's lust for power.