A: London, England, United Kingdom
Following the passage of the Census Act or Population Act of 1800, which he was largely responsible for drafting, English goverment official and statistician John Rickman supervised the first Census of England, Scotland and Wales— the first detailed census ever undertaken of any country.
"The 1801 census was in two parts: the first was concerned with the number of people, their occupations, and numbers of families and houses. The second was a collection of the numbers of baptisms, marriages and burials, thus giving an indication of the rate at which the population was increasing or decreasing. Information was collected by census enumerators who were usually the local Overseers of the Poor or (in Scotland) schoolmasters. They visited individual households and gathered the required information, before submitting statistical summaries. The details of households and individuals were important only in creating these local summaries and were destroyed in all but a few cases."
John Rickman first proposed the census in 1796 in an article in the Commercial, Agricultural, and Manufacturer's Magazine, which he edited. The Secretary to the Treasury, George Rose, noticed the article and in 1800 the Census Act, drafted by Rickman, was presented to parliament. Rickman then directed the census and was responsible for digesting and annotating the data.
The study of population was one of the major concerns of political economy at this time and the first census came at a crucial point in the debate. When Malthus published his Essay on Population in 1798, demographic knowledge was necessarily limited. After the results of the first census were known, Malthus extensively revised and expanded the Essay, incorporating insights gained from the census and other sources, and published it virtually as new work in 1803.
The census was published on December 21, 1801 as Abstract of the answers and returns made pursuant to an act, passed in the forty-first year of His Majesty King George III. Intitled an act for taking an account of the population of Great Britain, and the increase or diminution thereof. A second volume was published on June 9, 1802.