The first official census

There was widespread opposition to an official census until the end of the 18th century. This finally withered away after demographer Thomas Malthus, published his essay on the 'principle of population' in 1798.

Malthus caused great concern by suggesting that population growth would soon outstrip supplies of food and other resources. Unable to support itself, Britain would be hit by famine, disease and other disasters. Concerned at this alarmist view of the future, people began to see the need for a census. Parliament passed the Census Act in 1800 and the first official census of England and Wales was on 10 March 1801.

Information was collected from every household by the Overseers of the Poor, aided by constables, tithingmen, headboroughs and other officers of the peace. The Act also applied to Scotland, where the responsibility for taking the count was placed on schoolmasters. In Ireland, the first modern census was taken 20 years later, in 1821.

The first official head count revealed that Great Britain's population at the time was 9 million. Previous estimates had varied between 8 and 11 million. Information about every person in the land was processed by an army of clerks using nothing more than pens and paper. Technology made census taking simpler in 1911, when punch cards and mechanical sorting and counting machines were introduced. Computers were first used in the 1961 Census.

The registration service and the modern census

The census taken in 1841 is widely regarded as the first truly modern census, when the first Registrar General of England and Wales, John Lister, was made responsible for organising the count. The task of counting was passed on to local officers of the newly created registration service.

For the first time, the head of each household was given a form to fill in on behalf of everyone in the household on a certain day. This system has stood the test of time, and it still forms the basis of the method we use today. In Scotland there was no local registration service until 1855. A separate Act in 1860 gave the Registrar General for Scotland, responsibility for taking the 1861 Census. Prior to the passing of the Northern Ireland Census Act 1969, censuses in Northern Ireland were taken under the authority of separate Acts.

Since 1801 there has been a census every ten years except in 1941, during the Second World War. The basic principles of census taking remain the same, though new questions have been added and others have been omitted. Up until 1911 the Government needed to introduce a new Census Act for every census held. This was changed by the 1920 Census Act which made it possible for the Government to hold a census at any time, once Parliament has approved the necessary 'secondary' legislation which lays out the details of a particular census, but no sooner than five years after the last census.