NORTHUMBERLAND, the northernmost county of Eng land. The area, included in the North of England basin, is 2,018 square miles. The higher land, including the north Pennines and the Cheviots, lies in the west and north. The Cheviot hills, rising to 2,676 ft., are formed by the intrusion of an igneous dome in Ter tiary times, and between them and the northern Pennines we have the lower line of the Tyne Gap, giving an important way for routes from west to east. The larger rivers generally flow eastward, the chief exception being the Till which flows north ward, to join the Tweed, along a bed of shales less resistant than the remainder of the region.
The number of weapons of Neolithic age which have been found in the county show that it was occupied by man in those times. Most implements have been found along a broad band of country north-eastward from Hexham to Alnwick, that is, along the lower levels of the limestone lands. In later times, the evidence of beaker-pottery shows that Northumberland was probably invaded from across the North sea at the dawn of the Metal age. The evidence for the pre-Roman Iron age is not great and the Bronze age may have continued far longer than in the south of England. The county was occupied by the Romans some time after A.D. 8o and about 124. Hadrian built his wall from the Tyne to the Solway to defend his northern frontier, but the region as a whole was not thoroughly Romanized like the south-eastern parts of Britain. Hadrian's wall marked the frontier south of which the Romans never retreated until they finally left Britain, but they often advanced farther north which northern region was crossed by military roads. The wall ran across the county a few miles north of the Tyne from near Haltwhistle to Wallsend. On the wall there was the fort of Magnae, near Haltwhistle, where the road from Kirkby Thore along the south Tyne abutted on the wall. There was a settlement at Corbridge where the main road from the south crossed the Tyne and a fort near Halton where the road met the wall. At the eastern end of the wall there was a fort and another at Newcastle guarding a route across the Tyne.
Within the wall, from Halton to Magnae through the Tyne Gap, ran another road.
About the end of the 6th century Bernicia was first united with the rival kingdom of Deira under the rule of Aethelfrith, and the dis trict between the Humber and the Forth became known as the kingdom of Northumbria. In 634 Cadwalla was defeated at Hef en feld (the site of which lies in the modern parish of St. John Lee) by Oswald, under whom Christianity was definitely established in Northumbria, and the bishop's see fixed at Hexham, where Bishop Wilfrid erected the famous Saxon church. Oswald also erected a church of stone at Tynemouth, which was destroyed in 865 in an incursion of the Danes. The Danes later overran the region, but in Northumberland, the English princes continued to reign at Bamburgh as vassals of the Danes, and not a single place-name with the Danish suffix "by" or "thorpe" is found north of the Tyne. The English names are, however, often associated with those of Gaelic or Cymric origin. In 938 Aethelstan annexed Northumberland to his dominions, and the Danish authority was annulled until its re-establishment by Canute in 1013. The vigor ous resistance of Northumbria to the Conqueror was punished by ruthless harrying. The Normans rebuilt the Saxon monasteries of Lindisfarne, Hexham and Tynemouth ; Eustace Fitz John founded Alnwick abbey, and other Norman abbeys were Brinkburn, Hulne, the first Carmelite monastery in England, Blanchland and New minster. Castles were set up at Alnwick, Warkworth, Prudhoe, Dunstanborough, Morpeth, Ford, Chillingham, Langley, New castle, Bamburgh, Wark and Norham, a stronghold of the palatine bishops of Durham.