In post-Roman times the northwestern section of the county was possibly little better than a waste. It was not until the victory of Aethelfrith, near Chester in 613 cut off the Britons of Wales from those of Lancashire and Cumberland that even Lancashire south of the Ribble was conquered. The part north of the Ribble was not absorbed in the Northumbrian kingdom till the reign of Ecgfrith (67o-685). During the 9th century Lancashire was in vaded by the Danes, and after the peace of Wedmore (878) was included in the Danish kingdom of Northumbria. There are vari ous sculptured crosses, mostly of the 8th century or later, and a few traces of Celtic art. Scandinavian place names abound and indicate a wedge driven in between the Welsh of Wales and of Strathclyde. The A.S. Chronicle records the reconquest of the district between the Ribble and the Mersey in 923 by the English King, when it appears to have been united to Mercia, but the dis trict north of the Ribble still belonged to Northumbria until its incorporation with the kingdom of England. William the Con queror gave the lands between the Ribble and Mersey, and Amounderness to Roger-de-Poictou, but at the time of the Domes day Book these again belonged to the king.
The name Lancashire does not appear in Domesday; the lands between the Ribble and Mersey were included in Cheshire and those north of the Ribble in Yorkshire. Roger-de-Poictou soon regained his lands, and Rufus added the rest of Lonsdale south of the sands, and, as he had the Furness fells, he owned all that is now known as Lancashire. In 1102 he finally forfeited all his lands, which Henry I. held till, in '118, he created the honour of Lancaster, and bestowed it upon his nephew Stephen, afterwards King. During Stephen's reign difficulties arose, for David of Scot land held lands north of the Ribble for a time, and in 1147 the earl of Chester held the district between the Ribble and the Mer sey. Henry II. gave the whole honour to William, Stephen's son, but in 1164 it came again into the king's hands until 1189, when Richard I. granted it to his brother John. In 1194, it was con
fiscated and the honour remained with the crown till 1267. In 1229, however, all the crown demesne between the Ribble and Mersey was granted to Ranulf, earl of Chester, and on his death in 1232 came to William Ferrers, earl of Derby. The Ferrers held it till 1266, when it was confiscated. In 1267 Henry III. granted it to his son Edmund, who was created earl of Lancaster. His son, earl Thomas, married the heiress of Henry de Lacy, earl of Lincoln, and thus obtained the great estates belonging to the De Lacys in Lancashire. On the death of Henry, first duke of Lancaster, in 1361, the estates, title and honour fell to John of Gaunt, and by the accession of Henry IV., John of Gaunt's only son, to the throne, the duchy became merged in the crown.
The county of Lancaster is mentioned in 1169, as first contrib uting to the Royal Exchequer. The creation of the honour decided the boundaries. Ecclesiastically the whole of the county originally belonged to the diocese of York, but in 923 the district between the Ribble and the Mersey was placed under the Bishop of Lich field. Up to 1541 the district north of the Ribble belonged to the diocese of York. In 1541 the diocese of Chester was created and Lancashire was divided into two archdeaconnies. In modern times bishoprics have been established at Manchester, Liverpool and Blackburn and they divide the county between them, save that Furness and Cartmel were transferred to the diocese of Carlisle soon after that of Manchester was created.
No shire court was ever held for the county, but as a duchy and county palatine it has its own special courts. It may have enjoyed palatine jurisdiction under earl Morcar before the Con quest, but the first record of such privileges being exercised was in under Henry, duke of Lancaster. In 1377 the county was erected into a palatinate for John of Gaunt's life, and in 1396 these rights of jurisdiction were extended and settled in perpe tuity on the dukes of Lancaster. The county palatine courts con sist of a chancery which dates back at least to 1376, a court of common pleas, the jurisdiction of which was transferred in 1873 by the Judicature act to the high court of justice, and a court of criminal jurisdiction which in no way differs from the king's ordi nary court. In 1407 the duchy court of Lancaster was created, in which all questions of revenue and dignities affecting the duchy possessions are settled. The chancery of the duchy has been for years practically obsolete. The duchy and the county palatine have each its own seal. The office of chancellor of the duchy and county palatine, a crown office, dates back to 1351.