There have been churches on the site of the present St Mary’s since Saxon times, when The Green was a Saxon village. A Norman church was built in around 1160, and a few pieces remain, including an arch. It took the name St Mary’s in 1223.
When Marlborough was under a Royalist siege in 1642 the Parliamentarian commander took refuge in the church and the north side of the tower still bears the marks of shot from Royalist guns. The church was rebuilt by the Puritans after the Great Fire of Marlborough destroyed most of the town in 1653.
Among the interesting artefacts at the church is a statue of the Roman goddess Fortuna, thought to have originated from Roman Cunetio – now the nearby village of Mildenhall. It was built into the west wall of the nave during the 17th century rebuilding.