The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of the continental mainland. It comprises England, Scotland, Wales, and Northern Ireland. The UK includes the island of Great Britain, the north-eastern part of the island of Ireland, and most of the smaller islands within the British Isles, making up a total area of 94,354 square miles (244,376 km2). Northern Ireland shares a land border with the Republic of Ireland; otherwise, the United Kingdom is surrounded by the Atlantic Ocean, the North Sea, the English Channel, the Celtic Sea, and the Irish Sea. The United Kingdom had an estimated population of over 68.2 million people in 2023. The capital and largest city of both England and the United Kingdom is London, whose wider metropolitan area is the largest in Western Europe, with a population of 14.9 million. The cities of Edinburgh, Cardiff, and Belfast are the national capitals of Scotland, Wales, and Northern Ireland, respectively.
The population of the United Kingdom was estimated at 67,596,281 in 2022. It is the 21st most populated country in the world and has a population density of 279 people per square kilometre, 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 8,866,180 people in the capital city, London, whose population density was 5,640 inhabitants per square kilometre (14,600/sq mi) in 2022.
English is the most widely spoken and de facto official language of the United Kingdom. A number of regional and migrant languages are also spoken. Regional English variant languages are Scots and Ulster Scots; indigenous Celtic languages are Irish, Scottish Gaelic and Welsh. There are many non-native languages spoken by immigrants, including Polish, Punjabi, and Urdu. British Sign Language is sometimes used as well as liturgical and hobby languages such as Latin and a revived form of Cornish.
Coincident full censuses have taken place in the different jurisdictions of the United Kingdom every ten years since 1801, with the exceptions of 1941, Ireland in 1921/Northern Ireland in 1931, and Scotland in 2021. In addition to providing detailed information about national demographics, the results of the census play an important part in the calculation of resource allocation to regional and local service providers by the UK government.
The demography of Scotland includes all aspects of population, past and present, in the area that is now Scotland. Scotland had a population of 5,463,300 in 2019. The population growth rate in 2011 was estimated as 0.6% per annum according to the 2011 GROS Annual Review.
Hinduism is the third-largest religious group in the United Kingdom, after Christianity and Islam; the religion is followed by over one million people representing around 1.6% of the total population. According to the 2021 United Kingdom census Hindus are primarily concentrated in England, particularly in Greater London and the South East, with just under 50,000 Hindus residing in the three other nations of the United Kingdom. Hindus have had a presence in the United Kingdom since the early 19th century, as at the time India was part of the British Empire. Many Indians in the British Indian Army settled in the United Kingdom of Great Britain and Northern Ireland.
The United Kingdom Census of 1841 recorded the occupants of every United Kingdom household on the night of Sunday 6 June 1841. The enactment of the Population Act 1840 meant a new procedure was adopted for taking the 1841 census. It was described as the "first modern census" as it was the first to record information about every member of the household, and administered as a single event, under central control, rather than being devolved to a local level. It formed the model for all subsequent UK censuses, although each went on to refine and expand the questions asked of householders.
White British is an ethnicity classification used for the native White population identifying as English, Scottish, Welsh, Cornish, Northern Irish, or British in the United Kingdom Census. In the 2011 census, the White British population was 49,997,686, 81.5% of Great Britain's total population. For the United Kingdom entirely, due to different reporting measures within Northern Ireland which includes all those who identified as British with those who identified as Irish, an amalgamated total of 52,320,080 including those who identified as White Irish in Great Britain is given making up 82.8% of the population.
Mixed is an ethnic group category that was first introduced by the United Kingdom's Office for National Statistics for the 2001 Census. Colloquially, it refers to British citizens or residents whose parents are of two or more races or ethnic backgrounds. The Mixed or Multiple ethnic group numbered just under 1.8 million in the 2021 United Kingdom census or 2.7% of the total UK population.
Spaniards in the United Kingdom are people of Spanish descent resident in Britain. They may be British citizens or non-citizen immigrants. In the 2021 census for England and wales, 81,150 people self-identified as ethnic Spanish.
The term Other White, or White Other, is a classification of ethnicity in the United Kingdom, used in documents such as the 2021 United Kingdom Census, to describe people who identify as white persons who are not of the English, Welsh, Scottish, Roma, Irish or Irish Traveller ethnic groupings. In Scotland, the term Other White is also used to refer collectively to those not of Scottish or Other British ethnicity, in which case it also includes those of a Gypsy, Roma, Irish or Irish Traveller background.
The National Registration Act 1939 was an Act of Parliament in the United Kingdom. The initial National Registration Bill was introduced to Parliament as an emergency measure at the start of the Second World War.
A census of the population of the United Kingdom is taken every ten years. The 2011 census was held in all counties of the UK on 27 March 2011. It was the first UK census which could be completed online via the Internet. The Office for National Statistics (ONS) is responsible for the census in England and Wales, the General Register Office for Scotland (GROS) is responsible for the census in Scotland, and the Northern Ireland Statistics and Research Agency (NISRA) is responsible for the census in Northern Ireland.
The 2021 United Kingdom census is the 23rd official census of the United Kingdom. Beginning in 1801, they have been recorded every 10 years. The 2021 censuses of England, Wales, and Northern Ireland took place on 21 March 2021, and the census of Scotland took place 364 days later on 20 March 2022. The censuses were administered by the Office for National Statistics (ONS) in England and Wales, by the Northern Ireland Statistics and Research Agency (NISRA) in Northern Ireland, and by the National Records of Scotland in Scotland. These were the first British censuses for which most of the data was gathered online. Two of them went ahead despite the COVID-19 pandemic, in part because the information obtained would assist government and public understanding of the pandemic's impact. The census-taking in Scotland was postponed, and took place in 2022 because of the pandemic.
The United Kingdom Census 1931 was a census of the United Kingdom of Great Britain and Northern Ireland that was carried out on 26 April 1931. A census in Northern Ireland had been taken in April 1926, so no census was taken there in 1931. The questions asked were similar to those in 1921, with the addition of a question about everyone's usual place of residence, as opposed to where they actually were on that night.
White: Gypsy or Irish Traveller is an ethnicity classification used in the 2011 United Kingdom Census. In the 2011 census, the White: Gypsy or Irish Traveller population was 63,193 or about 0.1 per cent of the total population of the country. The ethnicity category may encompass populace from the distinct ethnic groups of Romanichal Travellers or Irish Travellers, and their respective related subgroupings, who identify as, or are perceived to be, white people in the United Kingdom.
James Galt was a Scottish medical missionary under the Church Mission Society. He is best known for founding the Church Missionary Society's opium hospital in Hangzhou, (Hangchow) China in 1871. The hospital continued to be operational and influential past 1948 and contained a medical school.
The 1841 Census of Ireland was a census that covered the whole island of Ireland. It was conducted as part of the broader 1841 United Kingdom census, which was the first modern census undertaken in the UK. The census is of particular note in Ireland as it was taken shortly before the Great Famine (1845-1852), which resulted in over 1 million deaths and spurred decades of mass emigration. The total population of the island in 1841 was estimated to be just under 8.2 million, which remains the highest recorded population Ireland has ever had. During this year, Ireland also held about 31% of the UK's population. As of the latest censuses – 2022 in the Republic of Ireland and 2021 in Northern Ireland – the island's population stood at just over 7 million, roughly 16% lower than its pre-famine peak.
England and Wales 
Scotland 
Jersey 
Guernsey and others
Isle of Man 
Great Britain (total)
Northern Ireland 
Irish Free State 
Ireland (total)