situation was transformed the following year when Alfred won a decisive victory over the Danes at the Battle of Edington. Ceolwulf is not recorded after 879. His successor as the ruler of the English western half of Mercia, Æthelflæd's husband Æthelred, is first seen in 881 when, according to the historian of medieval Wales, Thomas Charles-Edwards, he led an unsuccessful Mercian invasion of the north Welsh Kingdom of Gwynedd. In 883 he made a grant with the consent of King Alfred, thus acknowledging Alfred's lordship. In 886 Alfred occupied the Mercian town of London, which had been in Viking hands. He then received the submission of all English not under Viking control and handed control of London over to Æthelred. In the 890s, Æthelred and Edward, Alfred's son and future successor, fought off more Viking attacks. Alfred died in 899 and Edward's claim to the throne was disputed by Æthelwold, son of Alfred's elder brother. Æthelwold joined forces with the Vikings when he was unable to get sufficient support in Wessex, and his rebellion only ended with his death in battle in December 902. Sources The most important source for history in this period is the Anglo-Saxon Chronicle but Æthelflæd is almost ignored in the standard West Saxon version, in what F. T. Wainwright calls "a conspiracy of silence". He argues that King Edward was anxious not to encourage Mercian separatism and did not wish to publicise his sister's accomplishments, in case she became a symbol of Mercian claims. Brief details of her actions were preserved in a pro-Mercian version of the Chronicle known as the Mercian Register or the Annals of Æthelflæd; although it is now lost, elements were incorporated into several surviving versions of the Chronicle. The Register covers the years 902 to 924, and focuses on Æthelflæd's actions; Edward is hardly mentioned and her husband only twice, on his death and as father of their daughter. Information about Æthelflæd's career is also preserved in the Irish chronicle known as the Three Fragments. According to Wainwright, it "contains much that is legendary rather than historical. But it also contains, especially for our period, much genuine historical information which seems to have its roots in a contemporary narrative." She was praised by Anglo-Norman chroniclers such as William of Malmesbury and John of Worcester and she has received more attention from historians than any other secular woman in Anglo-Saxon England.