The earliest surviving parts of the church date to the Norman period. Other parts of the present Cathedral are post medieval or modern.
After the establishment of the new borough (Newport), the church remained just outside the boundary, within the Manor of Stow. The 1427 charter given to Newport identifies the graveyard of St Woolos as being on the boundary of Newport. At the end of the 11th century the church was given to the monastery of St Peter at Gloucester by Robert De Hay. The church was at times the centre of disputes over its rights, but it remained the parish church for the borough.
In later years, the Tithe Barn became a theatre for strolling players. The Stow Fair was held by the Cathedral on the Thursday of Whitsun and visitors from the fair would often visit the Barn to watch a play or comic act.
There is also evidence that the Barn later became a hospital and then a laundry, which served the children’s home situated in the adjoining houses. Indeed, there are still markings denoting the laundry visible on the building today.