Niklaus Mikaelson is an original vampire and a hybrid.
He is the son of an unnamed werewolf and Esther, the maternal younger half-brother of a deceased unnamed older half-brother, Elijah, and Finn, the maternal older half-brother of Kol, Rebekah, and Henrik, the step-son ofMikael, with whom he had an extremely bad relationship before he later killed the latter. Little is known about his werewolf side of the family due to Mikael's onslaught. He is also the father of a yet to be born Hybrid Child with Hayley Marshall, and a distant relative of Cary.
He is first mentioned in a conversation between Rose and Stefanwhen she warns him about the Originals. Elijah tells Elena that Klaus is believed to be the most hated and feared of all the Originals and those who fear him are desperate for his approval. Over the centuries, Klaus has become a recluse who confides in and trusts only the few members of his inner circle.
For over a thousand years, Klaus had been trying to break a curseplaced on him. He created the myth of the sun and moon curse in order to find the moonstone and the Petrova Doppelgänger, both of which were needed to break the actual curse. His goal was to liberate his werewolf side so he could sire his own super race of vampire-werewolf hybrids.
In 1492, he finally got his chance to break his curse when he metKaterina Petrova, the final piece necessary to break the curse. However, Katerina managed to foil his plan to use her in the sacrifice by turning into a vampire. For the next 500 years, Klaus searched for a way to break the curse without the doppelgänger, forcing generations of witches and warlocks to help him. During his search for a way to break the curse, Klaus hunted down his family and neutralized them. He also hunted Katerina Petrova, who had escaped him and stolen his moonstone.
He was the main antagonist of Season 2, making his first appearance in Know Thy Enemy, in Alaric's body. Season 3 also started with him and Stefan Salvatore as being the main antagonists, but by the end of the season he had become an anti-hero, withEsther and Alaric Saltzman being the main antagonists. He is also one of the supporting antagonists of Season 4. He is now the protagonist and lead role in The Originals and is now living in New Orleans.
He is close friends with Caroline, whom he is in love with, best friendswith Marcel, whom he works with in ruling New Orleans until Klaus discovered his treachery, for bringing Mikael to New Orleans. During the 1920's, Klaus formed a strong bond and brotherly relationship with Stefan Salvatore.
With Silas and Qetsiyah now deceased, Klaus is possibly the most powerful known supernatural creature in the series' universe. Klaus is also the first undead creature in the history of the series universe known to have impregnated a woman.
Klaus is a member of the Mikaelson Family, and a member of an unknown Family of Werewolves.
Klaus is an attractive man. His height is 5'11. Klaus possesses curled light-brown hair and light blue eyes that contrasts with his pearl-white skin. As a vampire and a warrior (10th century), he is well-built. Klaus possesses a delicate and yet masculine face, possibly due to the fact that he was once a nobleman in the 15th century.
Klaus' clothing style is quite casual, usually seen wearing shirts, jeans and jackets, although he can also use a more classic and refined outfit if the situation requires it (ex: the ritual of the moonstone; the Original ball thrown by Esther). He uses accessories, such as leather bracelets or necklace as seen in some scenes at the beginning of Season 3.