Ælfthryth, also known as Alfreda or Etheldritha, is revered as a saint in the Roman Catholic Church. She lived a life of devotion as a virgin and recluse, and she was the daughter of King Offa of Mercia.

According to a late and somewhat unreliable legend, Ælfthryth was supposedly betrothed to Saint Æthelberht. However, when Æthelberht arrived at the court of Offa to claim her, he was treacherously murdered, allegedly at the instigation of Cynethryth, Offa’s queen.^[2]

Later on, Ælfthryth retreated to the marshes of Crowland Abbey. By approximately 793, she had taken up residence in a cell, where she lived as a recluse until her death. Crowland Abbey asserted that her tomb was situated among those of the saints, alongside Guthlac of Crowland, but regrettably, her relics were said to have been lost in 870 during a Danish assault on the monastery. There is some conjecture about potential confusion with Ælfleda, another daughter of Offa, whose husband also met a tragic end through treachery.^[2]