The colonisation of South Australia occurred when the systematic collection of statistical information on people, which included their ages, occupations, education and religious beliefs, was becoming a responsibility of government. The first census of England and Wales took place in 1801, the first of New South Wales in 1828, and of Van Diemen's Land in 1841. In South Australia a simple tabulation of the inhabitants of Adelaide and adjacent districts was made in 1841. The first proper census was undertaken in 1844 and enumerated 17,366 persons, recording their age, sex, conjugal condition and occupation.
South Australia has recorded about 1,650,000 live births and 801,000 people have died during the 146 years from 1838 to 1984. In June 1985 the resident population was estimated at 1,362,880. Depending on the allowance made for those migrants who lived for a period in South Australia before departing elsewhere, it can be estimated that between 2,250,000 and 2,500,000 people have lived in South Australia since the advent of European settlement.
The size of the pre-European Aboriginal populations must remain conjectural, however, there is less uncertainty about the relative time spans of the Aboriginal and European occupations. Allowing twenty-five years for a human generation, there have been six generations of European South Australians compared with at least a thousand generations of Aborigines.
After the first census in 1844 officials in the office of the Colonial Secretary appear to have been anxious to record the quickening pulse of demographic growth and further censuses followed in 1846, 1850, 1855 and 1860. The 1860 census was scheduled for April Fool's Day and was treated by so many respondents in the spirit of the day that the results were invalid and a further count was called for on 7 April 1861. From then until 1881, South Australian censuses were held every five years, then every ten years until 1921. The Commonwealth government assumed responsibility for census taking after 1901, and in 1961 restored the five-year cycle which was first begun in South Australia.
The map shows the predominant religious adherence of people within rural local government areas in 1891 is a good example of the wealth of social information contained in the nineteenth-century censuses. Although the Church of England with 28% of the total population was then, as now, the largest denomination in South Australia, minority denominations were more strongly represented in most rural areas. Lutherans, although forming only 7.3% of the total population, were the dominant group in the closely settled Barossa Valley and adjacent areas and the eastern Mount Lofty Ranges. Methodists (Wesleyan, Primitive, and Bible Christians) formed 24% of the colony's population but dominated much of rural South Australia and the copper towns. Roman Catholics formed only 15% of the total population but were in a majority near Clare in the Mid North and on parts of the northeastern, drought-risky frontier of agricultural settlement.