The district was formed on 1 April 1974, under the Local Government Act 1972, as a merger of the Masham and Wath rural districts, and part of Thirsk Rural District, from the North Riding of Yorkshire, along with the boroughs of Harrogate and the city of Ripon, the Knaresborough urban district, Nidderdale Rural District, Ripon and Pateley Bridge Rural District, part of Wetherby Rural District and part of Wharfedale Rural District, all in the West Riding of Yorkshire.