Boann, whose name means “white cow,” is the Irish goddess of the River Boyne in Leinster, Ireland. A descendant of the Tuatha de Danann, she was married to either Nechtan, Elcmar, or Nuada, but her lover was the Dagda. To hide her affair, the Dagda made the sun stand still for nine months. This allowed for the conception and birth of Aengus in a single day.

Creator of the River Boyne, she defied her husband’s orders and approached the magical well of Segas. Surrounded by nine magic hazel trees, the well was home to the speckled salmon who ate the hazelnuts. Boann challenged the power of the well by walking counterclockwise, which caused the water to surge and rush towards the sea. The waters carried Boann, and she lost an arm, a leg, and an eye before eventually drowning in what is now the River Boyne.