In 1130, in a grand assembly of bishops, nobles, and in the presence of the king, Henry I., the Cathedral was consecrated.
As with many other cathedrals, fire wrought havoc in the sacred fane, especially in 1138 and 1177. The later Norman builders added much to the perfection of the church, carving the capitals of piers of the nave, recasing them, and building the west front, which Gundulf does not seem to have accomplished. After the fires the building was renewed, especially in the monks' quarters, which had suffered much. Another great misfortune was the plundering and devastation of the church by King John after his capture of the castle; but happily an event occurred which helped to fill the treasury of the monks, and enabled them to adorn their minster. One William of Perth, a baker by trade, who was of a pious mind, undertook a pilgrimage to the Holy Land, but was killed by robbers near Chatham, and buried here. Miracles were said to have been wrought at his tomb; the fame thereof spread; and crowds of pilgrims began to frequent St. William's shrine, and bring costly offerings. William de Hoo was sacrist and prior at the beginning of the thirteenth century, a most active builder, who rebuilt the choir and aisles, using much of the old Norman work. This choir was used for the first time in 1227. Another great builder was Richard de Eastgate, sacrist, who constructed a new west transept, and began the construction of the central tower. His work was continued, and before the century was completed there was a new south transept, and the piers finished for bearing the tower.
Bishop Glanville (1185-1214) was much hated by the monks, and continuous disputing arose. "He came from Northumbria," says a monk, "and is a proof of the saying that out of the north proceedeth all evil."
In 1264 Simon de Montfort and the barons besieged Rochester, and on Good Friday "the satellites of the devil entered the Church of St. Andrew with their drawn swords, and, striking fear and horror into its children and those also who had taken refuge in it, crucified them together with the Lord, Who suffereth in His elect. Moreover, they plundered the gold and silver and precious things. Some of the monks they imprisoned all the night, and armed men on their horses rode about the altars, and dragged thence with impious hands certain persons who had fled to them. The holy places--the chapels, cloisters, chapter-house, infirmary--were made stalls for their horses, and filled with filth and uncleanness."