Lulach was the step-son of Macbeth and he ruled Scotland briefly from August 1057 until March 1058. He was born in 1030 to Gruoch (Lady Macbeth) and her first husband the Mormaer (earl) of Moray. Gruoch was the grand-daughter of Kenneth III and her son Lulach was the last king of the Alpin dynasty.

He was also known by the unfortunate moniker Lulach the Simple and was killed by supporters of Malcolm III who followed him as king. Nothing much is known of his short reign.