Old English; earliest use found in The Blickling Homilies. Cognate with or formed similarly to Old Saxon heƀankuning from the Germanic base of heaven + the Germanic base of king. Compare Old Frisian himilkoning, Old Saxon himilkuning, Old High German himelchuning (Middle High German himilkünec, early modern German himmelskönig), and post-classical Latin rex caeli, rex caelorum, Old French rei del ciel. Compare King of heaven.