1915–1916 Church of England border polls
The Church of England border polls 1915–1916 were a series of referendums held in January and February 1915 (with second polls being held in two parishes in March 1916), for residents living in nineteen Church of England ecclesiastical parishes, the boundaries of which crossed the England–Wales border. They were carried out to determine if the parish residents wished their parish to remain part of the Church of England or to become part of the Church in Wales when the Welsh Church Act 1914 took effect.
Source: Wikipedia — 1915–1916 Church of England border polls (CC BY-SA 4.0)