Aethelred was very involved in the church. He and his wife Osthryth founded Bardney abbey in Lindsey. Queen Osthryth had the bones of her uncle, Oswald of Northumbria, brought to Bardney to be buried there. This caused some resentment by the monks who at first refused to accept his bones. But they were accepted and buried in the church with all the honors due a saint. Aethelred was a close friend of Wilfrid of York. In 691 Aethelred gave the bishop sanctuary in Mercia after his exile from Northumbria. While welcomed by Aethelred he was not by Queen Osthryth. Wilfred was an old enemy of her brother king Ecgfrith of Northumbria. But Ostryth was not completely accepted in Mercia. She created the cult of Saint Oswald in Mercia which did little to help Mercians forget old feuds with Northumbria. In 697, Queen Osthryth was murdered by Mercian noblemen. She was suspected of having some part in the murder of Peada forty years earlier. By this time she had become a nun and had given up married life. In 704 Aethelred stepped down as king to become a monk. His nephew Cenred became King after him. Aethelred retired to the monastery of Bardney where his wife Osthryth had been buried. He became the abbot of Bardney although he remained aware of Mercian politics. Two years after giving up the throne he called his nephew, King Cenred, to Bardsley to ask him to remain on good terms with his old friend Bishop Wilfrid. Aethelred died in 716.