1851 census

The United Kingdom Census of 1851 recorded the people residing in every household on the night of 30 March 1851, and was the second of the UK censuses to include details of household members. However, this census added considerably to the fields recorded in the earlier 1841 census, providing additional details of ages, relationships and origins, making the 1851 census a rich source of information for both demographers and genealogists.

The 1851 census for England and Wales was opened to public inspection in 1912 (the 100-year retainer rule was not in effect at the time), and has since been available from The National Archives as part of class HO107. The 1851 census for Scotland is available at the General Register Office for Scotland. An 1851 census was taken in Ireland but most of the records have been destroyed; those that remain are held by the Public Record Office of Northern Ireland (for those counties of Ireland which remain in the UK) or the National Archives of Ireland (for those counties now in the Republic of Ireland).

The 1851 census was the first to record the full details of birth location for individuals. Where 1841 had only recorded if an individual was born in a county, the 1851 census states the county and parish or town of birth as well. The purpose behind asking for this information was to answer one of the critical questions of the time which was the rate and intensity of migration from rural to urban areas. The results confirmed there had been a significant shift from the countryside to the towns.

The 1851 census was the first to record each person's marital status and relationship to the head of the household, as well as details of disability being recorded — with a field for recording the information that an individual was "blind, deaf or imbecile". Each individual's exact age was also recorded (to the nearest year) rather than rounding adult ages down to the nearest five years.

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