Currently being played by actor Simon Ward in the TV drama The Tudors (!) Stephen Gardiner was Bishop Of Winchester from 1531-1551 and 1553-1555. Gardiner was heavily involved in the divorce of Henry VIII from Katherine of Aragon and was appointed Bishop by Henry on the death of Cardinal Wolsey. Bishop Gardiner spent much of the reign of Edward VI as a prisoner in the Tower of London, due to opposing his Reform policies and remaining firm to the 'old religion' and during this time he was deprived of his bishopric. However after Edward's death he returned to favour under Queen Mary Tudor whom he crowned in 1553 and helped her to restore Catholicism, overturning the annulment of her parents’ marriage, making her legitimate, which was quite ironic bearing in mind his role in the original divorce! He officiated at her marriage to Philip of Spain at Winchester Cathedral on the 25th July 1554.
A chantry is a place within a church specially built for honouring and remembering important people buried there, there are 6 in the Cathedral. I have posted already on Bishop Fox's Chantry here.