Southwark Cathedral formally the Cathedral and Collegiate Church of St Saviour and St Mary Overie, is a Church of England cathedral in Southwark, London, near the south bank of the River Thames and close to London Bridge. It is the mother church of the Diocese of Southwark. It has been a place of Christian worship for more than 1,000 years, but the church was not raised to cathedral status until the creation of the diocese of Southwark in 1905.
Between 1106 and 1538, it was the church of an Augustinian priory, Southwark Priory, dedicated in honour of the Virgin Mary (St Mary – over the river, 'overie'). Following the dissolution of the monasteries, it became a parish church, with a dedication to the Holy Saviour (St Saviour). The church was in the diocese of Winchester until 1877, when the parish of St Saviour's, along with other South London parishes, was transferred to the diocese of Rochester. The present building retains the basic form of the Gothic structure built between 1220 and 1420, although the nave is a late 19th-century reconstruction.