The first castle was raised here at the time of the Norman Conquest and is mentioned in the Domesday Book in 1086. This early fortification was rebuilt for King William Rufus
Early records suggest that after the conquest, both the City and Castle of Rochester were awarded to the half-brother of King William, Odo, Bishop of Bayeux.
He is also said to have been responsible for the making of the Bayeux Tapestry, yet it was Odo who was the principal cause of the first great siege of Rochester Castle in 1088,Curiously the 1088 siege was not the result of an Anglo-Saxon uprising, but rather a dispute between the Normans themselves: after William’s death in 1087, his Anglo-Norman kingdom was split between his sons, and his barons, unhappy about the division, rose up against the new king of England, William II Rufus.
The castle that was disputed in Rochester in 1088 lacked the keep but it would have had the bank and ditch and stone curtain wall that survives today (though with substantial later additions). This outer wall that encloses the bailey made use of a corner angle of the former Roman wall of the city, along with the bank of the river Medway. Gundulf, bishop of Rochester, was responsible for its construction, as well as starting work on the adjacent Cathedral.
This GunduRochester Castle was fortified against the King and soon became a stronghold and headquarters for the rebels. The city was well placed for raids on London and it also enabled them to devastate the lands of Kent, particularly those belonging to Lanfranc, Archbishop of Canterbury, who had crowned Rufus and was therefore Odo's and the rebels' enemy. We are extremely fortunate in that the Chronicles of William of Malmesbury, Florence of Worcester and others survive, telling us much about this siege and of those who took part.
The Chronicler, Orderic Vitalis, tells us that in May 1088 Rufus set up two siege castles to block any exit from the beleaguered fortress and kept the rebels under constant attack. William of Malmesbury tells us that the garrison, under their leaders, Bishop Odo, Eustace the Younger of Boulogne and Robert of Belleme, son of Roger of Montgomery, earl of Shrewsbury, were constantly plagued by heat, flies and disease, and after a short period of great hardship, were compelled to seek terms of surrender, which Rufus reluctantly agreed upon.King John was not happy about Rochester being under the control of the Archbishop of Canterbury, and this arrangement was to fall apart in 1215. The next Archbishop, Stephen Langton, was disliked by John and he blocked his appointment to the position by Innocent III for several years. John was at first excommunicated for his actions, but eventually gave in and Langton took up his post in 1213. Langton played a leading role in the baronial opposition to John, and it was at his suggestion that the demands included in Magna Carta were modelled on the charter of Henry I.
The next phase of events at Rochester, leading up to the great siege of 1215
King John ordered his men to dig a mine under the South-East angle of the keep.They shored up the undermined Keeps foundations with wooden pit props.This was in a time before Gunpowder and they used the fat of 40 Pigs to help burn the pit props.It was succesful and a whole section of the South-Eastern Tower came crashing down.With the Keep breached King Johns men gained access.the Defenders withdrew behind the cross-wall of the Keep but were soon captured and tortured.shortly after his own release from confinement.


