Between 1500 and 1800, London grew to be the largest city in Western Europe, with its population growing almost 22 times larger in this period. London would eventually overtake Constantinople as Europe's largest in the 1700s, before becoming the largest city in the world (ahead of Beijing) in the early-1800s.

The most populous cities in this period were the capitals of European empires, with Paris, Amsterdam, and Vienna growing to become the largest cities, alongside the likes of Lisbon and Madrid in Iberia, and Naples or Venice in Italy. Many of northwestern Europe's largest cities in 1500 would eventually be overtaken by others not shown here, such as the port cities of Hamburg, Marseilles or Rotterdam, or more industrial cities such as Berlin, Birmingham, and Munich.

Chart and table of population level and growth rate for the London, UK metro area from 1950 to 2025. United Nations population projections are also included through the year 2035.

It is only in the past two centuries where demographics and the development of human populations has emerged as a subject in its own right, as industrialization and improvements in medicine gave way to exponential growth of the world's population. There are very few known demographic studies conducted before the 1800s, which means that modern scholars have had to use a variety of documents from centuries gone by, along with archeological and anthropological studies, to try and gain a better understanding of the world's demographic development. Genealogical records One such method is the study of genealogical records from the past; luckily, there are many genealogies relating to European families that date back as far as medieval times. Unfortunately, however, all of these studies relate to families in the upper and elite classes; this is not entirely representative of the overall population as these families had a much higher standard of living and were less susceptible to famine or malnutrition than the average person (although elites were more likely to die during times of war). Nonetheless, there is much to be learned from this data. Impact of the Black Death In the centuries between 1200 and 1745, English male aristocrats who made it to their 21st birthday were generally expected to live to an age between 62 and 72 years old. The only century where life expectancy among this group was much lower was in the 1300s, where the Black Death caused life expectancy among adult English noblemen to drop to just 45 years. Experts assume that the pre-plague population of England was somewhere between four and seven million people in the thirteenth century, and just two million in the fourteenth century, meaning that Britain lost at least half of its population due to the plague. Although the plague only peaked in England for approximately eighteen months, between 1348 and 1350, it devastated the entire population, and further outbreaks in the following decades caused life expectancy in the decade to drop further. The bubonic plague did return to England sporadically until the mid-seventeenth century, although life expectancy among English male aristocrats rose again in the centuries following the worst outbreak, and even peaked at more than 71 years in the first half of the sixteenth century.

National and subnational mid-year population estimates for the UK and its constituent countries by administrative area, age and sex (including components of population change, median age and population density).

Paris was Western Europe's largest city in 1650, with an estimated 400 thousand inhabitants, which is almost double it's population 150 years previously. In second place is London, with 350 thousand inhabitants, however it has grown by a substantially higher rate than Paris during this time, now seven times larger than it was in the year 1500. Naples remains in the top three largest cities, growing from 125 to 300 thousand inhabitants during this time. In the previous list, the Italian cities of Milan and Venice were the only other cities with more than one hundred thousand inhabitants, however in this list they have been joined by the trading centers of Lisbon and Amsterdam, the capital cities of the emerging Portuguese and Dutch maritime empires.

During the eighteenth century, it is estimated that France's population grew by roughly fifty percent, from 19.7 million in 1700, to 29 million by 1800. In France itself, the 1700s are remembered for the end of King Louis XIV's reign in 1715, the Age of Enlightenment, and the French Revolution. During this century, the scientific and ideological advances made in France and across Europe challenged the leadership structures of the time, and questioned the relationship between monarchial, religious and political institutions and their subjects. France was arguably the most powerful nation in the world in these early years, with the second largest population in Europe (after Russia); however, this century was defined by a number of costly, large-scale conflicts across Europe and in the new North American theater, which saw the loss of most overseas territories (particularly in North America) and almost bankrupted the French crown. A combination of regressive taxation, food shortages and enlightenment ideologies ultimately culminated in the French Revolution in 1789, which brought an end to the Ancien Régime, and set in motion a period of self-actualization.

War and peace

After a volatile and tumultuous decade, in which tens of thousands were executed by the state (most infamously: guillotined), relative stability was restored within France as Napoleon Bonaparte seized power in 1799, and the policies of the revolution became enforced. Beyond France's borders, the country was involved in a series of large scale wars for two almost decades, and the First French Empire eventually covered half of Europe by 1812. In 1815, Napoleon was defeated outright, the empire was dissolved, and the monarchy was restored to France; nonetheless, a large number of revolutionary and Napoleonic reforms remained in effect afterwards, and the ideas had a long-term impact across the globe. France experienced a century of comparative peace in the aftermath of the Napoleonic Wars; there were some notable uprisings and conflicts, and the monarchy was abolished yet again, but nothing on the scale of what had preceded or what was to follow. A new overseas colonial empire was also established in the late 1800s, particularly across Africa and Southeast Asia. Through most of the eighteenth and nineteenth century, France had the second largest population in Europe (after Russia), however political instability and the economic prioritization of Paris meant that the entire country did not urbanize or industrialize at the same rate as the other European powers. Because of this, Germany and Britain entered the twentieth century with larger populations, and other regions, such as Austria or Belgium, had overtaken France in terms of industrialization; the German annexation of Alsace-Lorraine in the Franco-Prussian War was also a major contributor to this.

World Wars and contemporary France

Coming into the 1900s, France had a population of approximately forty million people (officially 38 million* due to to territorial changes), and there was relatively little growth in the first half of the century. France was comparatively unprepared for a large scale war, however it became one of the most active theaters of the First World War when Germany invaded via Belgium in 1914, with the ability to mobilize over eight million men. By the war's end in 1918, France had lost almost 1.4 million in the conflict, and approximately 300,000 in the Spanish Flu pandemic that followed. Germany invaded France again during the Second World War, and occupied the country from 1940, until the Allied counter-invasion liberated the country during the summer of 1944. France lost around 600,000 people in the course of the war, over half of which were civilians. Following the war's end, the country experienced a baby boom, and the population grew by approximately twenty million people in the next fifty years (compared to just one million in the previous fifty years). Since the 1950s, France's economy quickly grew to be one of the strongest in the world, despite losing the vast majority of its overseas colonial empire by the 1970s. A wave of migration, especially from these former colonies, has greatly contributed to the growth and diversity of France's population today, which stands at over 65 million people in 2020.

This data collection of monthly and annual counts of burials from English parishes was created to investigate historical mortality regimes in England as part of a research project on Mortality, Migration and Medicalisation led by Richard Smith and Romola Davenport and its precursor pilot project led by Richard Smith on Short-term and spatial variations in infectious disease mortality. It comprises burial counts per month and year for 621 English parishes, for varying periods between 1528 and 1873. It also includes burial counts per month and year subdivided into adult or child (derived from family relationships eg son, daughter) for urban parishes in Leeds, Liverpool and also Birstall in Yorkshire West Riding and surrounding hinterland. There are separate annual burial counts by age group for all London (as one entity), derived from London Bills of Mortality. Data for 404 of the 621 parishes are from R S Schofield's English population history database distributed with a special 1998 issue of the journal Local Population Studies, also available as UKDA SN 4491, Parish Register Aggregate Analyses.

These counts of burials from English parishes were compiled as part of a research programme exploring long-run changes in England's mortality regime. Today, life expectancy is higher in urban rather than rural areas, but early modern towns and cities were demographic sinks with extraordinarily high mortality, especially among the young and migrants who were essential for city growth. The project investigated how and when cities transformed from urban graveyards into promoters of health between 1600 and 1945. The process of endemicisation and exogenous disease variation is key to the evolution of both urban and non-urban mortality regimes, especially with respect to: infectious diseases among the young, maternal health and adult migrants and their health/immunological status.

In 1500, the largest city was Paris, with an estimated 225 thousand inhabitants, almost double the population of the second-largest city, Naples. As in 1330, Venice and Milan remain the third and fourth largest cities in Western Europe, however Genoa's population almost halved from 1330 until 1500, as it was struck heavily by the bubonic plague in the mid-1300s. In lists prior to this, the largest cities were generally in Spain and Italy, however, as time progressed, the largest populations could be found more often in Italy and France. The year 1500 is around the beginning of what we now consider modern history, a time that saw the birth of many European empires and inter-continental globalization.

In each decade between 1629 and 1830 in London, smallpox was responsible for a significant portion of all deaths; having a share of nine or ten percent in the second half of the eighteenth century. After this peak, the discovery of vaccination by Edward Jenner in 1796 helped to bring this share of deaths back down to a similar share it had in the mid-1600s. The lack of statistical data from these early decades makes it difficult to explain why smallpox's share of total deaths was lower than the decades where inoculation (known as "variolation" when referring to smallpox) was in practice throughout Britain, after its introduction in the 1720s; this is possibly due to the impact of other infectious diseases from the time (for example, the bubonic plague was present in England until the late seventeenth century) or possibly the misreporting of data.

In 2024, gross domestic product per capita in the United Kingdom was 36,977 British pounds, compared with 37,028 pounds in the previous year. This was the second-consecutive year that GDP per head has fallen in the UK, with the measure shrinking by 0.9 percent in 2023. In general, while GDP per capita has grown quite consistently throughout this period, there are noticeable declines, especially between 2007 and 2009, and between 2019 and 2020, due to the Global Financial Crisis, and COVID-19 pandemic, respectively. Why is GDP per capita falling when the economy is growing? During the last two years that GDP per capita fell in the UK, the overall economy grew by 0.4 percent in 2023 and 0.9 percent in 2024. While the overall UK economy is therefore larger than it was in 2022, the UK's population has grown at a faster rate, resulting in the lower GDP per capita figure. The long-term slump in the UK's productivity, as measured by output per hour worked, has meant that the gap between GDP growth and GDP per capita growth has been widening for some time. Economy remains the main concern of UK voters As of February 2025, the economy was seen as the main issue facing the UK, just ahead of immigration, health, and several other problems in the country. While Brexit was seen as the most important issue before COVID-19, and concerns about health were dominant throughout 2020 and 2021, the economy has generally been the primary facing voters issue since 2022. The surge in inflation throughout 2022 and 2023, and the impact this had on wages and living standards, resulted in a very tough period for UK households. As of January 2025, 57 percent of households were still noticing rising living costs, although this is down from a peak of 91 percent in August 2022.

In the 3 years to March 2021, black households were most likely out of all ethnic groups to have a weekly income of under £600.

In 2023/24 there were 1,699 food bank distribution centers run by the UK's main food bank distributor, the Trussell Trust, compared with 1,646 in the previous year. In this year, over 3.12 million people used a food bank in the UK, compared with just under 26,000 in 2008/09.

Life expectancy in the United Kingdom was below 39 years in the year 1765, and over the course of the next two and a half centuries, it is expected to have increased by more than double, to 81.1 by the year 2020. Although life expectancy has generally increased throughout the UK's history, there were several times where the rate deviated from its previous trajectory. These changes were the result of smallpox epidemics in the late eighteenth and early nineteenth centuries, new sanitary and medical advancements throughout time (such as compulsory vaccination), and the First world War and Spanish Flu epidemic in the 1910s.

The fertility rate of a country is the average number of children that women from that country would have throughout their reproductive years. In the United Kingdom in 1800, the average woman of childbearing age would have five children over the course of their lifetime. Over the next 35 years the fertility rate was quite sporadic, rising to over 5.5 in the 1810s and 1820s, then dropping to 4.9 by 1835. This was during and after the Napoleonic Wars and the War of 1812 with the US, which was a time of increased industrialization, economic depression and high unemployment after the war. As things became more stable, and the 'Pax Britannica' (a period of relative, international peace and economic prosperity for the British Empire) came into full effect, the fertility rate plateaued until 1880, before dropping gradually until the First World War. The fertility rate then jumped from 2.6 to 3.1 children per woman between 1915 and 1920, as many men returned from the war. It then resumed it's previous trajectory in the interwar years, before increasing yet again after the war (albeit, for a much longer time than after WWI), in what is known as the 'Baby Boom'. Like the US, the Baby Boom lasted until around 1980, where it then fell to 1.7 children per woman, and it has remained around this number (between 1.66 and 1.87) since then.

At the beginning of the 1840s, life expectancy from birth in Ireland was just over 38 years. However, this figure would see a dramatic decline with the beginning of the Great Famine in 1845, and dropped below 21 years in the second half of the decade (in 1849 alone, life expectancy fell to just 14 years). The famine came as a result of a Europe-wide potato blight, which had a disproportionally devastating impact on the Irish population due to the dependency on potatoes (particularly in the south and east), and the prevalence of a single variety of potato on the island that allowed the blight to spread faster than in other areas of Europe. Additionally, authorities forcefully redirected much of the country's surplus grain to the British mainland, which exacerbated the situation. Within five years, mass starvation would contribute to the deaths of over one million people on the island, while a further one million would emigrate; this also created a legacy of emigration from Ireland, which saw the population continue to fall until the mid-1900s, and the total population of the island is still well below its pre-famine level of 8.5 million people.

Following the end of the Great Famine, life expectancy would begin to gradually increase in Ireland, as post-famine reforms would see improvements in the living standards of the country’s peasantry, most notably the Land Wars, a largely successful series of strikes, boycotts and protests aimed at reform of the country's agricultural land distribution, which began in the 1870s and lasted into the 20th century. As these reforms were implemented, life expectancy in Ireland would rise to more than fifty years by the turn of the century. While this rise would slow somewhat in the 1910s, due to the large number of Irish soldiers who fought in the First World War and the Spanish Flu pandemic, as well as the period of civil unrest leading up to the island's partition in 1921, life expectancy in Ireland would rise greatly in the 20th century. In the second half of the 20th century, Ireland's healthcare system and living standards developed similarly to the rest of Western Europe, and today, it is often ranks among the top countries globally in terms of human development, GDP and quality of healthcare. With these developments, the increase in life expectancy from birth in Ireland was relatively constant in the first century of independence, and in 2020 is estimated to be 82 years.

In January 2025, the top one percent of earners in the United Kingdom received an average pay of 15,882 British pounds per month, compared with the bottom 10 percent of earners who earned 813 pounds a month.

There were estimated to be 217,000 same-sex couple families in the United Kingdom as of 2022, compared with just 16,000 in 1996.