Answer
Æthelwold, Ealdorman of East Anglia, was instrumental in securing territories for Edward the Elder's father, Alfred the Great. He played a pivotal role in the Battle of Edington, a decisive victory that marked a turning point in Wessex's struggle against the invading Danes. Æthelwold's military prowess and strategic alliances made him a key figure in expanding Wessex's influence and consolidating Alfred's power.