The last Saxon cathedral burnt down in 1067 and, following his appointment in 1070, Archbishop Lanfranc completed the first phase of the romanesque cathedral by 1077. The nave was on the current footprint and accommodated the choir in its eastern bays because the sanctuary and side aisles terminated in semi circular apses extending only a few metres east of the central tower. Between 1093 and 1109, under Archbishop Anselm and Priors Ernulf and Conrad, the cathedral was substantially extended to the east to provide a much larger choir and sanctuary with western transepts, two radial chapels and a small eastern axial Trinity chapel, all on the current footprint.
In 1174, only four years after the murder of Archbishop Thomas Becket, a fire destroyed the roof and badly damaged the upper stonework of the arcade and walls of the choir, chapels and transepts. They were rebuilt in the period 1175-84 in a transitional gothic style known as early English. This included a further eastward extension to replace the original axial chapel with a much larger version, to contain the shrine of St Thomas Becket, and beyond that a circular corona chapel. An ambulatory and parclose screen was provided around the perimeter of the choir and sanctuary to allow the monks to continue their divine service whilst retaining access to the shrine for pilgrims. This was all the work of William of Sens, who brought expertise in the gothic style from the rebuilding of Sens cathedral, and his successor William the Englishman. The two striking features of the rebuilding are the raising of the trinity chapel to a higher level to give prominence to the shrine of St Thomas Becket and the way it is pinched between the romanesque radial chapels which remained. A more subtle feature of the rebuilding is the integration of the surviving round arched windows of the romanesque external walls and the new gothic arcade, triforium, clerestorey and vaults with their pointed arches and ribbing. It was during this rebuilding that most of the medieval glass remaining in the cathedral was installed. The body of St Thomas Becket was eventually translated to his new shrine from his tomb below in 1220, for which the current St Augustine’s chair standing behind the altar was commissioned.
In the period 1298-1305 Prior Eastry constructed a new parclose screen to surround the choir in the gothic decorated style which can still be seen today, although much has been cut away to accommodate later tombs. In 1336 this was followed by a new window in St Anselm’s chapel, also in the decorated style. Pilgrims continued to visit the shrine until its destruction under the orders of King Henry VIII in 1538.
The post reformation history following the dissolution of the monastery in 1540 is one of neglect and vandalism and destruction, particularly of altars, tombs, paintings, sculpture, chapels and stained glass by reformers, followed by improvements in the contemporary style of the times and more recently enlightened restoration.