Elijah Mikaelson was the third-born of Mikael and Esther's children. He was the younger brother of Freya and Finn Mikaelson, and the older brother of Kol, Rebekah and Henrik Mikaelson. Elijah was also the older half-brother of Niklaus Mikaelson.

To ensure that the rest of her family would survive, when the Werewolves killed Henrik, Esther used a spell to make her children immortal, turning them into the first vampires. After Esther died, Elijah and Klaus made a pact with Rebekah that they would stick together as one, always and forever. Elijah spent most of his life honoring that pack, which Klaus made very difficult.

In the 21st century, Elijah developed feelings for Hayley Marshall. He was deeply saddened by her death. When Klaus was forced to kill himself in order to protect his daughter, Elijah decided to die by Klaus' side, as his life's purpose to redeem Klaus was fulfilled. They stake each other and both turn to ash.