The origins of Christianity in this part of England go back at least to the 7th century, when Saint Birinus brought his mission to the West Saxons in 634.

The West Saxon King Cynegils was baptised in the River Thames near the present site of Dorchester Abbey, where the original See was established.

The see was transferred in 1092 to Winchester, before being absorbed into the Diocese of Lincoln, the vast extent of which covered much of central and eastern England from the River Thames to the Humber.

While the city gained prosperity from the accession of thousands of students, it was never, apart from the university, again prominent in history until the seventeenth century, when it became the headquarters of the Royalist party, and again the meeting-place of Parliament.

The modern diocese covers the counties of Oxfordshire, Berkshire, and Buckinghamshire, with parishes also in Bedfordshire, Gloucestershire, Hampshire, Hertfordshire, and Warwickshire.