The census records information on the country's population and has been taken every ten years since 1801, with the exception of 1941. The returns of most use to the family historian are those from 1841 onwards. From 1861, the gathering of Scottish census material has been the responsibility of the General Register Office for Scotland. Records may only be inspected after 100 years, so the census returns presently available for public scrutiny are 1841-1901. During the period 1801 to 1831 the Census was carried out by local Parish Schoolmasters. Unfortunately most of these records prior to 1831 were destroyed. There were a few which did survive, mainly for parishes in Orkney, and by checking local libraries, they may be able to tell you if they exist and where.
The census is essentially a snapshot of the people in a household on a given night and as such can provide details of a particular family and anyone else who happens to be in the house at the time, for example, servants, lodgers, or visitors. Census records can be used, not only to further your search for direct ancestors, but also to broaden your knowledge of the wider family and to bridge the gap between statutory and OPR records. They can also give an indication of how the family lived. Geographic mobility can be tracked through the given birthplaces, and social mobility through addresses and occupations.
In theory, every person should have been enumerated where they actually were on the night of the census was taken, but where people were 'on the move' or visiting someone, they were often completely missed by the enumerators or in a few cases, they were enumerated twice.
Scottish Census dates were:1911 2nd April
1901 31st March
1891 5th April
1881 3rd April
1871 2nd April
1861 7th April
1851 30th March
1841 6th June
The above census details are available at www.scotlandspeople.gov.uk, and for free although more limited, at www.familysearch.org.
The gathering of census information in Scotland in 1851 took place under the jurisdiction of the Home Office, and was organised by the sheriffs and chief magistrates. All subsequent censuses have been conducted by the office of the Registrar General for Scotland, established under the 1854 Registration of Births, Deaths and Marriages (Scotland) Act. Census enumerators were appointed and assigned a specific area to cover, distributing a schedule to every household in that area before census night. They then collected the completed schedules the following day, checked the details and copied them into an enumerator's book. The census information that we see derives from the enumerators' transcript books, not the original schedules, which were destroyed.