A military survey of Didmarton in 1522 shows that it was then a very small village, overshadowed by the neighbouring Oldbury-on-the-Hill.
In the 16th century, the manor of Didmarton was owned by the Seacole family. In 1571, Simon Codrington married Agnes, daughter and co-heiress of Richard Seacole, and the estate thus passed to their son Robert Codrington. It was sold to Charles Somerset, 4th Duke of Beaufort, in about 1750, but has had a succession of other owners since then.
Together with Oldbury, the parish was subject to enclosure in 1829. In 1883, the civil parish of Oldbury-on-the-Hill was abolished and the area merged with Didmarton.
A 19th century description
A Vision of Britain through Time provides the following description of Didmarton from John Marius Wilson's Imperial Gazetteer of England and Wales of 1870-72:
Parish registers from 1674 to 1991 are held at the Gloucestershire Record Office.
Surnames in the marriages register for 1675 to 1751 are: Acton, Allen, Biggs, Bishop, Brooks, Brush, Burcombe, Byrton, Carey, Chapman, Chappel(l), Codrington, Collings, Davies, Drew, Emely, Frith, Gingill, Harris, Hatchett, Heaven, Iddols, Kingscott, Lewis, Milsum, Minchin, Porter, Powel, Power, Robbins, Scrope, Shipton, Smart, Sparkes, Taunton, Thompson, Walls, Watts, Weekes, White, and Witchell.
The surnames recorded in the parish graveyard, and in that of the Didmarton Congregational church, include: Baker, Bickerton, Borham, Cox, Gould, Lucas, Pritchard, Short, Rice, Robbins, Till, and Tuck.