Cwenthryth of Mercia (also given as Cwoenthryth, 9th century CE) was the daughter of King Coenwulf (r. 796-821 CE). Little is known of her actual life but she later became infamous in the 12th century CE through the legend of St. Kenelm as the scheming sister who arranges her brother Kenelm's death. There is no historical basis for this legend and the casting of Cwenthryth as villainess was most likely due to the historical Cwenthryth's dispute with Wulfred, Archbishop of Canterbury between c. 805-832 CE, and a later scribe's poor opinion of a woman challenging the authority of the church.
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