During the development of the South Wales coalfield and Cardiff Docks, the parish was gradually absorbed into the Borough of Cardiff during the 19th and 20th centuries. Seen as a clean and green up-market countrified village location close to the fast developing city, many of the better-off coal merchants and business people chose to live in Llandaff, including the Insole family. The house now known as Insole Court dates originally from 1856. Llandaff itself became a civil parish, and from 1894 to 1922, was part of the Llandaff and Dinas Powis Rural District. On 9 November 1922, the county borough of Cardiff was extended to include the area.