The Romans were the first to settle

The Romans were the first to settle and occupy the Celtic fortress of Londinium. Construction of a bridge in 100 A.D. made London an important junction: it soon became a busy commercial and administrative settlement, and in the 2nd century A.D. a wall was built round the city.
The Roman Empire fell in the 5th century. London have maintained its trading activity. In the 9th century Danish invaders destroyed much of the city. They were followed by the Saxons led by King Alfred the Great, who entered the city in 886. The Danes remained a powerful force in England, however, and it was not until the reign of Edward the Confessor, which began in 1042, that civic stability was re-established, to be cemented by the Norman Conquest in 1066.
William the Conqueror centred his power at the Tower of London, and his White Tower is still the heart of this impressive monument.
The City soon united its economic power with political independence. Late in the 12th century it elected its own Lord Mayor. From 1351 it elected its own council, and by the end of the 14th century the reigning sovereign could not enter the City without permission.
In the reign of Elizabeth I had the arts a renaissance with such great dramatists as Shakespeare, Marlowe, and Ben Jonson.
In 1665, London had been devastated first by the Great Plague, and then by the Fire of London, which destroyed most of the city the following year. During the reconstruction of the city, following the original street pattern, the architect Sir Christopher Wren was given responsibility for the design of a number of State-funded buildings, including St. Paul's Cathedral.
The western part of London was developed under the Hanoverian Kings: great squares were laid out such as those of Grosvenor, Cavendish, Berkeley, and Hanover, and more bridges were built across the river. Public services were improved, such as the water supply and sewerage systems, and the streets were paved.
In the 19th century London's population began to rise still more rapidly: it increased sixfold over the century as a whole, thanks to influx from all over the British Isles, from Britain's colonies, and from continental Europe. The Industrial Revolution was creating huge numbers of jobs, but never enough to satisfy the hopes of all the poor people who came to the capital. The novels of Charles Dickens tell us about the social problems of that period.
The First World War had little effect on London, but the Depression that followed in the late 1920s and early 1930s hit the whole country, including the capital. There were hunger marches and riots. London was to pay far more dearly during World War II. The intensive bombing of London (The Blitz) in 1940-1941 took the lives of 10,000 people and left 17,000 injured. Countless historic buildings were damaged, including the Houses of Parliament.
After the war London was to re-emerge as a radically different city. The docks had been so severely damaged that reconstruction, a very expensive process, was not reasonable. By the end of the 1950s most of the war damage had been repaired. New skyscrapers were built, outdoing each other in height and spectacular design. The 30-storey Post Office Tower was built in 1965. It is 189 m high. Other significant post-war developments include the 183 m National Westminster Bank Building (1979); and Britain's highest building, the 244 m Canary Wharf Tower on the Docklands site, near to a new City airport.