Cwenthryth (Old English: Cwēnþrȳð) was an early 9th-century Mercian princess, the daughter of Coenwulf of Mercia and sister of Saint Cenelm. After Coenwulf's death, his son was killed fighting the Welsh, possibly due to Cwenthryth's treachery.
She was also the Abbess of Minster-in-Thanet who inherited property and authority from King Coenwulf of Mercia. Wulfred, Archbishop of Canterbury, challenged her for authority of her abbey estates, and they fought each other for control.
- Salmonson, Jessica Amanda, The Encyclopedia of Amazons (Paragon House, 1991), 66. ISBN 1-55778-420-5