The Victorian era was a time of unprecedented demographic increase in Britain. The population rose from 13.9 million in 1831 to 32.5 million in 1901.
Two major factors affecting population growth are fertility rates and mortality rates. Britain was the first country to undergo the Demographic transition and the Agricultural and Industrial Revolutions.
Britain had the lead in rapid economic and population growth. At the time, Thomas Malthus believed this lack of growth outside Britain was due to the ‘Malthusian trap’. That is, the tendency of a population to expand geometrically while resources grew more slowly, reaching a crisis (such as famine, war, or epidemic) which would reduce the population to a sustainable size. Britain escaped the ‘Malthusian trap’ because the Industrial Revolution had a positive impact on living standards. People had more money and could improve their standards; therefore, a population increase was sustainable.
In the Victorian era, fertility rates increased in every decade until 1901, when the rates started evening out. There are several reasons for the increase in birth rates. One is biological: with improving living standards, the percentage of women who were able to have children increased. Another possible explanation is social. In the 19th century, the marriage rate increased, and people were getting married at a very young age until the end of the century, when the average age of marriage started to increase again slowly. The reasons why people got married younger and more frequently are uncertain. One theory is that greater prosperity allowed people to finance marriage and new households earlier than previously possible. With more births within marriage, it seems inevitable that marriage rates and birth rates would rise together.
Birth rates were originally measured by the ‘Crude birth rate’ – births per year in population per every thousand people. This is thought not to be accurate enough, as key groups and their fertility rates are not clear. It also does not take into account population changes, e.g., same number of births in a smaller population (if men go to war, etc.). It was then changed to the ‘Net Reproduction Rate,’ which only measured the fertility rate of women who were capable of giving birth.
The evening out of fertility rates at the beginning of the 20th century was mainly the result of a few big changes: availability of forms of birth control, and changes in people’s attitude towards sex.
The mortality rates in England changed greatly through the 19th century. There was no catastrophic epidemic or famine in England or Scotland in the 19th century – it was the first century in which a major epidemic did not occur throughout the whole country, with deaths per 1000 of population per year in England and Wales dropping from 21.9 from 1848–54 to 17 in 1901 (contrasting with, for instance, 5.4 in 1971). Class had a significant effect on mortality rates as the upper classes had a lower rate of premature death early in the 19th century than poorer classes did.
Environmental and health standards rose throughout the Victorian era; improvements in nutrition may also have played a role, although the importance of this is debated. Sewage works were improved as was the quality of drinking water. With a healthier environment, diseases were caught less easily and did not spread as much. Technology was also improving because the population had more money to spend on medical technology (for example, techniques to prevent death in childbirth so more women and children survived), which also led to a greater number of cures for diseases. However, a cholera epidemic took place in London in 1848–49 killing 14,137, and subsequently in 1853 killing 10,738. This anomaly was attributed to the closure and replacement of cesspits by the modern London sewerage system.