What is "ealhswith"

Ealhswith or Ealswitha (died 5 December 902) was the wife of King Alfred the Great. Her father was a Mercian nobleman, Æthelred Mucil (or Mucel), Ealdorman of the Gaini, which is thought to be an old Mercian tribal group. Her mother was Eadburh, a member of the Mercian royal family, and according to the historian Cyril Hart she was a descendant of King Coenwulf of Mercia.