By Tim Lambert
About 650 BC a people called the Celts migrated to Britain. Then in 43 AD, the Romans invaded. It is impossible to accurately estimate the population of Britain before the Romans came. However, the population of Roman Britain was probably about 4 million.
Roman towns would seem small to us. The largest town, London, may have had a population of only 35,000. Roman Colchester probably had a population of around 12,000. Roman Cirencester may have had a population of 10,000.
In the 4th century, Roman civilization declined and in 407 AD the last Roman soldiers left England. Afterward, the population shrank. (It may have fallen to less than half its Roman level). That may have been partly due to a terrible plague that struck Europe in the 6th Century).
The population of Ireland in 43 AD is not known but an educated guess is about 1/2 million. It was probably not more than 3/4 million.
After the Romans departed Germanic peoples, the Angles, Saxons, and Jutes landed in England and gradually conquered it. However many Celts survived and were assimilated into Saxon society. However, the Saxons never gained effective control of Cornwall.
Another great wave of invasion came in the 9th century. The Danes conquered North and Eastern England. At that time England was divided into kingdoms and the only one left was the southern kingdom of Wessex led by Alfred the Great. Alfred eventually defeated the Danes and they made a treaty. They split southern and central England between them. The Danes took London, East Anglia, and all the territory east of the old Roman road, Watling Street.
Alfred took the land west of Watling Street and southern England. However, in the 10th century, Wessex gradually expanded and took over all the Danish territory. So a single united England was created. The Danish settlers gradually assimilated into English society.
At the time of the Domesday Book (1086) England probably had a population of about 2 million. (Much less than in Roman times). However, the population grew rapidly. It may have reached about 5 or 6 million by the end of the 13th century.
In the Middle Ages, most people lived in the countryside and made a living from farming. However, at the time of the Domesday Book (1086) about 10% of the population of England lived in towns. Moreover, trade boomed in the following two centuries, and many new towns were founded.
The first thing that would surprise us about those towns would be their small size. At the time of the Domesday Book in 1086 London had a population of about 18,000. By the 14th century, it rose to about 45,000. Other towns were much smaller. York may have had a population of about 13,000 by 1400 but it then fell to about 10,000 by 1500. Most towns had between 2,000 and 5,000 inhabitants.
However, disaster struck in 1348-49 when the Black Death reached England. It killed about 1/3 of the population. The plague returned again and again and the population of England was severely reduced. In 1400 the population of England was probably about 2 1/2 million.
By 1530 the population of England and Wales had risen to around 3 million and by 1600 it was about 4 million. In Tudor times towns remained small (although they were a vital part of the economy). The only exception was London. From a population of only about 60,000 or 70,000 at the end of the 15th century, it grew to about 250,000 people by 1600. Other towns in Britain were smaller. The next largest town was probably Bristol, with a population of only around 20,000 in 1600.
Nevertheless in the 16th century towns grew larger as trade and commerce grew. The rise in town’s populations was despite outbreaks of plague. It struck all the towns at intervals in the 16th and 17th centuries but seems to have died out after 1665. Each time it struck a significant part of the town’s population died but they were soon replaced by people from the countryside.
At the end of the 17th century, it was estimated the population of England and Wales was about 5 1/2 million. The population of Scotland was about 1 million. The population of London was about 600,000.
In the mid-18th century the population of Britain was about 6 1/2 million. In the late 18th century it grew rapidly and by 1801 it was over 9 million. The population of London was almost 1 million.
During the 18th century towns in Britain grew larger. Nevertheless, most towns still had populations of less than 10,000. However, in the late 18th century new industrial towns in the Midland and the North of England mushroomed.
Meanwhile, the population of London grew to nearly 1 million by the end of the century. Other towns were much smaller. The population of Liverpool was about 77,000 in 1800. Birmingham had about 73,000 people and Manchester had about 70,000. Bristol had a population of about 68,000. Sheffield was smaller with 31,000 people and Leeds had about 30,000 people. Leicester had a population of about 17,000 in 1800. In the south, Portsmouth had a population of about 32,000 in 1800 while Exeter had about 20,000 people.
In the 19th century, Britain became the world’s first industrial society. It also became the first urban society. By 1851 more than half the population lived in towns.
The population of Britain boomed during the 19th century. In 1801 it was about 9 million. By 1901 it had risen to about 41 million. This was despite the fact that many people emigrated to North America and Australia to escape poverty. About 15 million people left Britain between 1815 and 1914.
However, there were also many immigrants. In the 1840s many people came from Ireland, fleeing a terrible potato famine. In the 1880s the Tsar began persecuting Russian Jews. Some fled to Britain and settled in the East End of London.
During the 20th century, the population of Britain grew more slowly. However, by the beginning of the 21st century, it had reached 60 million. In the 1950s large numbers of West Indians arrived in Britain. Also from the 1950s, many Asians came. In the late 20th century Britain became a multicultural society.
Meanwhile, the population of London reached a peak of 8.7 million in 1939. It fell to just under 8.2 million in 1951 and it has since fallen to 7.2 million.
In 2021 the population of Britain was 68 million.
Last revised 2023