East Harnham, upstream of Britford, was a tithing of Britford parish until All Saints' church was built there in 1854, and a district chapelry created for it the next year.
Historically, East Harnham was part of Britford parish until the construction of All Saints' Church in 1854, at which point it became a distinct entity with its own chapel and subsequent district chapelry established the following year.