The manor of Cnaresburg is mentioned in Domesday as the private demesne of the Conqueror, as it had been of the Confessor. Nothing is said of an “Aula” or a castle there; but, as eleven Berewicks depended upon it, it is clear that it was, during, and probably long before, the time of Edward, the centre of a considerable estate, and if, as was usual, its early lord had there a fortified residence, it would naturally be placed upon the rugged and knotty platform that bore the descriptive name of Cnaresburg. William granted the manorial lands, returned in Domesday as “wasta,” to Serlo de Burg, Burg being probably the manor now called Boroughbridge. Burg was a territorial designation, not a regular surname, and does not appear to have been used by the family. The Pipe Roll, 31 Henry I., 1130, mentions Serlo as holding lands in Notts and Derby, and gives the names of Osbert, his son, and of another Osbert, his “nepos” or nephew, both of whom seem to have died before their respective fathers. The successor and heir of Serlo was John the One-eyed, whose son, Eustace Fitz-John, was a Yorkshire Justiciar. He appears in the same Pipe Roll as farming Burg and Chenardesburg, and to him was then allowed £11 for the king’s works, evidently upon the castle, at the latter place. Eustace married Beatrice, a De Vesci heiress, and their son William assumed that name. Richard FitzEustace, another son, married Albreda, the daughter and heir of Robert de Lisours, by Albreda, sister of Ilbert and Henry de Lacy, and aunt and heir of Robert de Lacy of Pontefract, who died childless, 1193. In consequence, Roger, Constable of Chester, the son of Richard FitzEustace and Albreda, took and transmitted the name of Lacy. Eustace had also a brother, Pain Fitz-John, a considerable Herefordshire landowner, and ancestor of the Barons FitzPain. With Eustace, who fell in the Welsh wars in 1159, the family occupation of the castle ceased, and it was from time to time granted by the Crown to various castellans. One of these, Hugh de Morville, took refuge here after the murder of Beckett. It was held also by the Estotevilles, and, in the reign of John, by Brian de Lisle, who is reputed to have excavated the castle ditch, and to have repaired or added to the buildings. Henry III. granted the castle to Hubert de Burgh in fee. Before that time the manor had been erected into an Honour, and the Honour, the Peculiar, and the forest of Knaresborough are from time to time the subject of royal grants. In 1257, Henry III. gave them to his brother Richard, who founded a priory on the river bank below the castle. Edward II. repeated the grant to Gaveston, about which time the Slingsbys appear as keepers of the forest. In 1327, the castle was taken for the Earl of Lancaster, but only to be resumed by Edward III., who, in 1371, granted it to John of Gaunt, and it has ever since formed a part of the Duchy of Lancaster. Richard II. was imprisoned here in 1399, and the keep has since borne