In 658, Coenred's father Wulfhere came to the throne of Mercia as the result of a coup, ending a three-year period of Northumbrian control. Wulfhere was succeeded on his death (in 675) by his brother Æthelred, Coenred's uncle, possibly because Coenred was too young to rule. Coenred's mother Ermenilda became a nun sometime after Wulfhere's death. Æthelred's decisive victory over the Northumbrians at the Battle of the Trent in 679, followed by the Picts' destruction of the Northumbrian army at the Battle of Dun Nechtain in 685, reduced Northumbrian power and influence. There is evidence of Mercian activity in the south-east as well. Æthelred invaded Kent in 676, and charters survive in which he confirmed land grants made by Swæfheard and Oswine, kings of west and east Kent. Another charter of Æthelred's, dated between 693 and 704, grants land to Waldhere, the bishop of London. However, Æthelred does not appear to have sought expansion further south. The growing strength of the West Saxons under Cædwalla and Ine would have limited Mercian opportunities in that direction.