Cambridgeshire, Lincolnshire, Northamptonshire, Suffolk, Sussex, and Yorkshire were split up for administrative purposes, following historical divisions used by the Courts of Quarter Sessions.

The Isle of Wight was previously administered as part of Hampshire but became its own administrative county in 1890.

Monmouthshire, not shown on the map, was reckoned for some legal purposes among the English counties for most of this period.

The reasons for this were threefold: the growth of towns on either side of an existing boundary, the creation and extension of county boroughs and the elimination of outlying exclaves and other anomalies.

As urbanisation increased, and suburbs were built on a scale not seen before, the urban areas surrounding various towns and cities started to cross traditional county borders.

Towns that were split by historic borders and were unified in one administrative county include Banbury, Mossley, Tamworth, Todmorden.

The boundaries of Gloucestershire, Worcestershire and Wiltshire contained numerous enclaves and exclaves, and were realigned in 1931.

Throughout the next century, debates took place about what should be done about local government in respect of the increasing urbanisation of the country.

The County of London was abolished, and replaced by Greater London, a sui generis council area, taking the three of the surrounding county boroughs, more of Surrey and Kent, parts of Essex and Hertfordshire and consuming nearly all of Middlesex – the remaining parts being ceded to Surrey and Hertfordshire.

Some other changes took place, such as the Soke of Peterborough and Huntingdonshire being merged into Huntingdon and Peterborough, and the merger of the original Cambridgeshire with the Isle of Ely to form Cambridgeshire and Isle of Ely.