Earl of Northumbria was a title in the Anglo-Danish, late Anglo-Saxon, and early Anglo-Norman period in England. The earldom of Northumbria was the successor of the ealdormanry of Bamburgh, itself the successor of an independent Bernicia. Under the Norse kingdom of York, there were earls of Deira. Eventually all Northumbria was united under the Bernician dynasty. This dynasty held onto Bernicia until 1041, but from 1016 there were other earls in York who were appointed by King Canute the Great over all Northumbria. It was itself broken up in the early Norman period and dissolved into the earldoms of York and Northumberland, with much land going to the prince-bishopric of Durham.
The earls were:
Osulf I (954-963), Earl of Bernicia from 930
Oslac of Northumbria, exiled in 975
Waltheof I (963-995)
Uhtred the Bold (1006-1016)
Eric of Hlathir (1016-1023)
Siward (1031-1055), without underlings in Bernicia from 1041
Osulf II (1067)
Robert Comine (1068-1069)
Vacant during the Harrying of the North until...
Gospatric (1070-1072, again
Waltheof II (1072-1075)
William Walcher (1075-1080), also prince-bishop of Durham
Aubrey de Coucy (1080), perhaps formally until 1086
Robert de Mowbray (1086-1095)
Vacant until Stephen was pressured by David of Scotland to grant to ...
Henry of Scotland, 1139-1152
William of Scotland, 1152-1157
Deprived of title and lands by Henry II of England, 1157
Purchased by Hugh de Puiset, the Bishop of Durham in 1189, and held until 1191 or so.
Vacant until the First Barons' War, when the barons of Northumberland and York did homage to ...
Alexander II of Scotland, 1215-1217
Surrendered to Henry III of England, 1217