Demographics of the United Kingdom
The population of the United Kingdom was estimated at 69.3 million in 2024. It is the 21st most populated country in the world and has a population density of, with England having significantly greater density than Wales, Scotland, and Northern Ireland. Almost a third of the population lives in south east England, which is predominantly urban and suburban, with people in the capital city, London, whose population density was in.
The population of the UK has undergone demographic transition— from a typically pre-industrial population, with high birth and mortality rates and slow population growth, through a stage of falling mortality and faster rates of population growth, to a stage of low birth and mortality rates with, again, lower rates of growth. This growth through 'natural change' has been accompanied in the past three decades by growth through net immigration into the United Kingdom, which since 1999 has exceeded natural change.
The United Kingdom's high literacy rate of 99% at age 15 and above, is attributable to universal state education, introduced at the primary level in 1870 and at the secondary level in 1900. Parents are obliged to have their children educated from the ages of 5 to 16 years. In England, 16–17-year olds should remain in education, employment or training in the form of A-Levels, vocational training, and apprenticeships, until the age of 18.
The United Kingdom's population is predominantly White British, but due to migration mostly from Commonwealth nations, Britain has become ethnically diverse. The second and third largest non-white racial groups are Asian British at 8.6% of the population, followed by Black British people at 3.71%.
The main language of the United Kingdom is British English. Scots is widely spoken in many parts of Scotland, as is Scottish Gaelic, a Celtic language. Cornish and Irish have been revived to a limited degree in Cornwall and Northern Ireland, but the predominant language in all these areas is English. Welsh is widely spoken as a first language in parts of North and West Wales, and to lesser extent in South East Wales, where English is the dominant first language.
History
Before the census, 200–1800
had an estimated population between 2.8 million and 3 million at the end of the second century AD. At the end of the fourth century, it had an estimated population of 3.6 million, of whom 125,000 consisted of the Roman army and their families and dependents. The urban population of Roman Britain was about 240,000 people at the end of the fourth century. Roman Britain's capital city, Londinium, is estimated to have had a population of about 60,000.Following the Roman withdrawal from Britain, Germanic tribes from continental Europe such as the Angles, Saxons and Jutes began a period of significant migration to the southeastern part of the island, notably bringing their language, Old English. Nevertheless, the overall population is believed to have fallen precipitously due to political upheavals and plagues. By the time of the compilation of the Domesday Book in the eleventh century, there may have between 1.25 and 2 million people living in England. Though the Domesday Book did not count the English population, it has been regarded as one of the first attempts to produce a census of the country.
Between the years of 1086 and 1750, the English population fluctuated in size due to civil war, famines and plagues. By the end of the 13th century, the population was estimated to have reached between four and six million people. A combination of factors such as widespread famine and disease in the following century collapsed the population dramatically. An agricultural crisis in 1315 to 1322 and the Black Death in 1348 to 1350 collapsed the population by over a third of its pre-existing number, and the growth rate. In 1377, the population was estimated via a poll-tax of all people aged 14 and over, depending on the population amount of those under 14, to be around 2.2 million to 3.1 million.
Periods of instability over the 15th century, such as the Wars of the Roses, caused the population to increase at a slower pace. The general factors behind this were a high mortality rate due to war, fewer marriages within the population, late marriages and a net emigration of English people out of the country. By the 16th century, the situation had changed due to political stability under the Tudor monarchy and little civil unrest, which would have resulted in a higher mortality rate. While this was overturned with the English Civil War in 17th century, it allowed the population to grow at a faster pace, causing the population of England to reach a pre-collapse total of 5.74 million by 1750.
In Scotland, population growth was not to the same extent as it was in England, which resulted in being significantly lower in the late 17th and early 18th centuries, which is often ascribed to similar factors halting it such as a high mortality rate, especially for infants, and later marriage and childbearing patterns. Ireland before the 19th century consistently had rapid population growth, which has been ascribed to higher fertility rates and earlier age of marriage than in England. The Plantation of Ulster in the 17th century also affected the population of Scotland, with an estimated 100,000 Scots migrating to Ulster. The Jacobite rebellion in 1745 also caused significant emigration. The estimated population total of Scotland in 1691 was 1.23 million.
The impetus to collect population data was reinforced due to food supply concerns and war against France in the late 18th century and the beginning of the early 19th century. In 1800, the Census Act was passed, authorising the first modern census in British history to be conducted.
Census established and the demographic transition, 1800–2000
The first Census in 1801 revealed that the population of Great Britain was 10.5 million. England's population was 8.3 million, Wales' population was 0.6 million, and Scotland had a population of 1.6 million. In Ireland, the population was between 4.5 and 5.5 million inhabitants. Since 1801, a census has been conducted almost every decade. In Ireland, it was conducted for the first time in 1821.During the Industrial Revolution, the demographic transition started in the United Kingdom, going from a pre-industrial society demographically to an industrialised society. At the 1841 Census, the population of England and Wales was 15.9 million, having doubled in the space of 40 years. Ireland had 8.2 million and Scotland had 2.6 million. The slightly lower rate of growth for Scotland may be attributed to higher net emigration of Scottish people out of the nation, and two typhus epidemics in 1837 and 1847.
Factors often associated with the beginning of the demographic transition began to change dramatically as well, which contributed to the rapid increase. For example, child mortality decreased dramatically: the proportion of children born in London who died before the age of five decreased from 74.5% in 1730–1749, to 31.8% in 1810–1829. General mortality was thought to have declined as well, especially after 1850. This, as well as an increased birth rate, caused the English population to sustain itself in the second phase of the transition from 1750 to 1870.
In the second half of the 19th century the population of England continued to grow quickly, from 16.8 million in 1851 to 30.5 million in 1901. This rapid growth was seen in the other constituent nations. In Wales, the population increased from 0.6 million in 1801, to 2 million in 1901. In Scotland, the population increased from 1.6 million in 1801, to 4.5 million in 1901. In contrast, the Great Irish Famine, which began in the 1840s, caused the deaths of 1 million Irish people, and caused well over a million to emigrate.
Mass emigration became entrenched as a result of the famine, and Ireland's population decreased rapidly, from 8.2 million in 1841 to 3.2 million in 1901. This massive population collapse did not affect Northern Ireland to the same extent, as it was more industrialised and urbanised. While the Northern Ireland population declined, it recovered by the beginning of the 20th century. This prolonged period of emigration and net population decline in Irish history was not reversed until the middle of the 20th century.
The total fertility rate of the UK population declined from 4.88 children per woman in 1871, to 2.4 by 1921, representing a transition to the third stage of the demographic transition. Traditional means of birth control, such as abstinence and withdrawal, facilitated the collapse of the birth rate. By the 1930s, this was hastened by more modern methods of contraception, which were beginning to gain increased acceptance. From 1840 to 1930 there was a net emigration of English people out of the country, which scaled back population growth.
During the first half of the 20th century, the United Kingdom began to approach the fourth stage of the demographic transition. The deaths of troops in the First World War, coupled with the 1918 influenza outbreak, are estimated to have totalled over 900,000 deaths in the United Kingdom. This reduced the male population of the Lost Generation and altered the sex ratio, which slowed the growth rate of the population. By the end of the Second World War, the fourth stage transition was completed. There was a low but fluctuating birth rate, a low death rate and a slower population growth rate. The British Nationality Act 1948 allowed many people from the British Empire's colonies to migrate to the country, being classed in nationality as the same as a native of the United Kingdom. This law, while an unintentional side-effect, led to the start of modern immigration to the United Kingdom.
In the 1960s, there was also major social change in the United Kingdom. Liberalisation of society led to the Abortion Act 1967, which legalised abortion in the United Kingdom for the first time, and the Divorce Reform Act 1969, which made divorce easier. Between these years, the population fluctuated: from the 1950s onwards the population increased through natural growth. By the mid-1970s, the population decreased due to emigration, which took net migration to a negative, and deaths exceeded births. For the first time in 1973, the birth rate of the country fell below replacement level. By the 1980s, the decline of population growth had recovered to an extent due to a reversal of net emigration.
In the 1990s, international migration began to contribute more to population growth. In 1998, this overtook natural increase as the main cause of growth. Liberalisation of immigration rules under the Blair government allowed a rapid increase of the number of migrants arriving, quadrupling the number from a net migration rate of 50,000 a year, to 200,000 a year.