Although the three authorities govern separately, the county remains one ceremonial county.
The county borders the counties of Cambridgeshire to the northeast, Northamptonshire to the north, Buckinghamshire to the west and Hertfordshire to the southeast. It also borders the historic county of Huntingdonshire to the northeast, which has been administered as part of Cambridgeshire since 1974.
For more information, see the EN Wikipedia article History of Bedfordshire., especially the sections "Political history", "Sub county level administration" (which lists the civil parishes and urban and rural districts in charge at various times) and "Industry and agriculture".
Ancient Parishes and Registers
Bedfordshire contains 131 parishes, the parish registers of a dozen of which began before 1540. Most parishes were in the archdeaconry of Bedford in the parish of Lincoln until 1837. The archdeaconry was then transferred to the diocese of Ely and has been in the diocese of St Albans since 1914. A few parishes were transferred between Bedfordshire and Hertfordshire in 1844 and 1899. (source: Genuki pages for Bedfordshire)
English Jurisdictions 1851
Family Search maps have provided this finding aid or "app". Type a location in the search box, select Parish, County, Civil Registration District, Diocese, Rural Deanery, Poor Law Uniion, Hundred or Division from the pulldown list and you are provided with a box locating the place on a Google map. The Info tab gives the dates of creation of the parish, its predecessor(s) and the availability of Parish Records and Bishops Transcripts. The Jurisdictions tab gives the Civil Registration District, the Probate Court, the Diocese, the Rural Deanery, the Poor Law Union, the Hundred and the Ecclesiastical Province. Under options you have a choice of listing contiguous parishes, doing a radius place search, searching the Family History Catalog, the Family History Historical Records, or the FamilySearch Research Wiki, or simply moving on to another search. A layer system allows you to search under more than one category at a time. Remember that history “stops” at 1851 on this finding aid.