St Mary's stands in the physical centre of the old walled City, and the university grew up around it. In medieval times scholars lived in houses with their teachers and the university had no buildings of its own, so it adopted St Mary's as its centre. The church continued as a parish church, but by the early 13th century it had become the seat of university government, academic disputation, and the awarding of degrees.
By the 14th century, as colleges were beginning to be founded, the expanding university, desperately in need of more room for its business, constructed the Old Congregation House (c. 1320), a small building of two storeys, on the north-east side of the church, abutting the tower. The House was built with money left by Bishop Cobham for that purpose, and to house his boooks. Thus the upper room became the first university library, containing a small number of chained books, and also the place where the university's money was kept in the university chest. The lower room, which now houses the cafe, was used by the university's 'parliament'.
All university business was removed from the church by the middle of the 17th century, but St Mary's remains the place where the university formally comes to worship. On two Sundays during term time, the formal university sermon is preached here, before the vice-chancellor and proctors, who enter with full ceremonial procession to their throne-like seats at the back of the nave.
The Oxford Martyrs
Each of the three anglican bishops, Latimer, Ridley and Cranmer, who were burnt at the stake in Oxford during the reign of the Roman Catholic queen, 'Bloody Mary', underwent part of his trial in St Mary's. Their principal crime was not to believe the doctrine of transsubstantiation, although Cranmer, as Henry VIII's Archbishop, had also played a crucial role in the downfall of Queen Mary's mother, Catherine of Aragon.
The three men were first tried in April 1554 in the chancel. Ridley and Latimer were again tried here in 1555 before their martyrdom on 16 October - a fearful sight, watched by Cranmer from the roof of his prison, the 'Bocardo', which was at the North Gate adjacent to St Michael's Church in Cornmarket. The place of martyrdom is marked by a cross in the centre of Broad Street, outside Balliol College.
John Wesley, founder of Methodism, often attended the University Sermon in his Oxford days, and subsequently, as a Fellow of Lincoln College, preached some of his most stirring sermons before the University here - notably the famous sermon the 'Almost Christian' in 1741. In 1744, again in St Mary's, he denounced the laxity and sloth of the senior members of the University. He was never asked to preach here again. 'I have preached, I suppose,' I wrote, 'the last time in St Mary's. Be it so. I am now clear of the blood of these men. I have fully delivered my soul.'
Newman and The Oxford Movement
The present pulpit and furnishings were installed by the University in 1827. Galleries were erected on the north and west walls, creating in the nave an auditorium which could seat a huge congregation. Onto this stage, in 1828, stepped a new vicar, John Newman, Prize Fellow of Oriel College, thought by some to be the most intelligent man in Oxford. Undergraduates flocked to his sermons. Writing 40 years later, Matthew Arnold, who had been an undergraduate in Newman's time, asked, 'Who could resist the charm of that spiritual apparition, gliding in the dim afternoon light through the aisles of St Mary's, rising into the pulpit, and then, in the most entrancing of voices breaking the silence with words and thoughts which were a religious movement, subtle, sweet, mournful?'
It was however, the Assize Sermon of 14 July 1833, preached by John Keble, the Professor of Poetry, from the present pulpit, which is considered to have launched the famous 'Oxford' or 'Tractarian' Movement, This was an attempt by a group of dons (all clerics at that time) to revive catholic spirituality in the church and University. In this Newman's leadership was central. The influence of the movement spread out of Oxford, and in subsequent decades had a radical effect on the spirituality and practice of the Church of England. The name 'Tractarian' derives from the 'Tracts for the Times' - a series of leaflets written by Newman and others to disseminate their ideas.
However, by 1843, Newman was disillusioned with anglicanism and resigned from St Mary's. He was soon to be accepted into the Roman Catholic Church, and in 1879 became one of its cardinals.