Catholicism was the form of Christian tradition in England until Henry VIII fell out with the Pope. From that point on a turbulent history began for any professing the Roman Catholic way as the true way. Until the Catholic Emancipation Act of 1829 in it was illegal to be a Roman Catholic although many had continued to practice their faith resulting in confiscation of land and property and much persicution. Even after the Act Roman Catholics were not able to sit university exams or hold office in one. For this reason there will be virtually no records of any buildings or people connected to Roman Catholicism, in the conventional manner of registers and minutes of meetings.
It was thought that there was no Catholic tradition in Tetbury but research undertaken by Father Breen, the Archivist of the Fransalians, makes reference to a notebook of Father Larive who lists his Tetbury parishioners and the work being done in the town. This can be read in fullhere.
The return of any form of Roman Catholic worship in Tetbury didn't happen until 1935 when the Salesians based at Malmesbury opened a branch house, with a chapel, at a house in Silver Street. A separate parish for Tetbury was founded in the following year, and in 1942 the former Baptist chapel at the Green was opened as St. Michael's Catholic church.
The following year the church was registered for solemnising marriages.
The chuch webpages have a very good history available as well as the list of priests from 1941 to the present day. An obituary for Msg. W.Mitchell who died in 2008 can be found here.
'Commodious premises' in Silver Street, known as York House were bought by the RC Authorities with a view to establishing a church in the town, although it was expected that the scheme would take some time. York House had previously been used as a private school