Æthelred II, known as Æthelred the Unready ( – 1016), was King of the English from 978 to 1013 and again from 1014 to 1016.
Æthelred II or Ethelred II may also refer to:
Æthelred II of East Anglia, king 870s Æthelred II of Northumbria, king 840s/850s