In the twenty years immediately preceding the arrival of Augustine, the long line of British Bishops of London came to an end. It has been a subject of remark, and of moralising, that Theonus, the last bishop, lost heart and fled just when the chance was coming for which it is presumed that he had been waiting, the actual beginning of the conversion of the English. But remarks of this character are misplaced; they disregard--or are ignorant of--the political facts of the time. Theonus of London was a British bishop in a British city. London had not fallen. Most difficult of access in the then state of land and water, of marsh and mud, whether from north or south or east or west, it held out to the last. The earliest date that can be assigned to its fall is about the year 568, and a date so early as that is only given to account for Ethelbert's being able to take his army from Kent to Wimbledon without interruption from London. But for that, and there may be other explanations of it, it is quite possible to put the taking of London by the East Saxons a few years later. But it is not necessary for our purpose. The date of the flight of Theonus has been said to be 586. It is probable that this is about the date of Ethelbert's vigorous action northwards, by which he made himself over-lord of his East Saxon neighbours and of London their most recent conquest, which they appear not to have occupied for some years after its fall. The political and administrative changes, due to this expansion of the power of Kent, may well have made ruined London no longer a possible place of residence, and of work, for a Christian Briton so prominent in position and office as the Bishop of London must always have been. It seems probable that Matthew of Westminster was not far wrong when he wrote that in 586 Theonus took with him the relics of the saints, and such of the ordained clergy as had survived the perils, and retired to Wales. Others, he says, fled further, to the continental Britain. Thadioc of York, he adds, went at the same time. In some parts, as for instance about Glastonbury, the British Christians remained undisturbed by the English for sixty or seventy years longer[32].