It is not known for sure why the nuns ended up settling at Princethorpe. It may well have been down to luck that the right site was available at the right time. As well as affording the level of seclusion that was desirable to the enclosed community, the natural springs and good farmland allowed the Priory to be self-sufficient. Laws preventing the building of religious houses had also been recently repealed making Princethorpe Priory one of the first new Catholic buildings in England in 300 years. Princethorpe may also have been chosen because Warwickshire had a history of wealthy landed families remaining loyal to their Catholic beliefs even after the Reformation so there may also have been plenty of support available, both spiritually and financially.
Using a paste model of the layout of the original priory in Montargis as the basis for the design, building of the priory began under the supervision of John Craven with the foundation stone being laid by Thomas Walsh, Titular Bishop of Cambysopolis, in 1832. The first party from Orrell Mount moved to St Mary’s Priory, Princethorpe, in 1835; the same year that the first pupils joined the school. John Russell joined the project in 1836 and, along with Craven, focused on the north and west wing and the original church. The church was later adapted by Joseph Aloysius Hansom who appears to have replaced John Russell in 1837, when Russell became ill.
Hansom was to have a significant impact on the design of the priory. Alongside finishing the chapel, he also built ‘Le Tour’ as a guest house for visitors to the priory, named for the small crenelated towers that form part of the design. He also built the Round House as a nuns’ cemetery after razing an existing structure on the site. The final resting place of ninety sisters and a small number of lay people, the circular brick design with an open roof is unknown anywhere else in Britain. In 1891, Joseph Pippet created the ornate ‘Death of St Benedict’ mural that is still visible in the Library today.