Daughter of King Cador of Northumberland in Girart d'Amien's Escanor. Her father threw a tournament at Banborc to find her a husband. Sir Cey (Cei), who later became better known as the Arthurian knight Sir Kay, distinguished himself in the tournament and fell in love with Andrivete, but, bashful, he returned to Arthur's court without confessing his affections.
On her father's death her uncle, Ayglin, tried to get rid of her by marrying her off to someone unsuitable, a commoner. Kay learned of her plight, returned to Banborc, rescued Andrivete and married her. She prepared to overthrow her uncle, supported by her husband, and in later accounts with the support of King Arthur, but before any fighting could break out the people of Northumberland forced him to surrender before any violence could occur, and Andrivete regained her kingdom.
Originally a story with only local Northumbrian significance, this story later passed into the Arthuria cycle because of the presence of Cei, or Sir Kay, in the story.
In a romance preceding Girart's, Andrivete is proven unfaithful by a chastity test at Arthur's court involving a mantle.