At the start of the 20th century London was a larger, busier place than it had ever been before. A thriving centre of trade and commerce, and at the hub of the world’s largest empire. Giant liners crossed the oceans and electric lighting was beginning to appear.

The terrific population growth of the late Victorian period continued into the 20th century. In 1904 the first motor bus service in London began, followed by the first electric underground train in 1906, but perhaps more notable was the spate of new luxury hotels, department stores, and theatres which sprang up in the Edwardian years, particularly in the West End. The Ritz opened in 1906, Harrod's new Knightsbridge store in 1905 and Selfridges in 1907.

But in the early part of the century, for poorer Londoners, there was little difference between this London and the city of fifty years before. Queen Victoria was still on the throne; there was still dire poverty, and those who were without work had to survive on charity and scavenging. As in many periods before, London was a mixture of ostentatious wealth and desperate poverty.

With the outbreak of the first world war, not for the first time, London faced the direct blows of an enemy. In the Autumn of 1915 the first Zeppelin bombs fell near the Guildhall, killing 39. Londoners were outraged and called the Zeppelins the ‘baby killers’. Towards the end of the war London suffered a more sustained and accurate bombing campaign and, in all, 650 fatalities resulted from bombings during the "war to end all wars". This was an early foretaste of what was to come just a few of decades later.

Public transport expanded a great deal in the first quarter of the century, with tramlines being laid and omnibus routes being established. London's population surged again after the war, to around 7.5 million in 1921. The London County Council began building new housing estates, which pushed London further and further out into the countryside. John Betjeman's ‘Metroland’ was born, named after the Metropolitan Line, whose trains entered the Hertfordshire countryside and brought the suburbs with them.

In the early 1920's unemployment was high, and labour unrest erupted in the 1926 General Strike. So many workers joined the strike that the army was called in to keep the Underground and buses running, and to maintain order. In the early 1930's this was followed by the the depression and the growing unease about what was happening in Germany.

The '30's also saw large numbers of Jews fleeing persecution in Europe and moving to London's West End. Then in 1938 there was more movement, this time out of the city. The threat from Germany was growing and large numbers of children were moved out of London to the surrounding countryside.

World War II was probably the defining moment of the century for Londoners, as with it came the Blitz. Since the great fire of 1666 the skyline of London had changed only gradually; there was a sense of permanence. The first world war had not had a major impact on London, but the second world war changed the city completely. During the dark days of 1940 over a third of the City was destroyed by German bombs, and the London Docks were almost completely demolished.

As bombs rained down nightly on London the East End felt the brunt of it, but the whole of London suffered. Those people who had to stay in London during the hours of darkness made a nightly descent into public shelters or the underground stations, often emerging to streets which were very different from the ones they had passed on their way down.

Some 16 acres around the area that now houses the Barbican development and the Museum of London were totally flattened, and numerous historic buildings were destroyed. The death toll was heavy; 32,000 dead and over 50,000 badly injured.

After the destruction of war came a feeling of optimism and renewal as the rebuilding began. Another feature of the post-war period was heavy immigration from the countries of the old British Empire. This changed the character of many parts of the city; Notting Hill acquired a large Caribbean community, Honk Kong immigrants settled in Soho, Sikhs in Southall and Greek Cypriots in Finsbury.

In 1951 the Festival of Britain was held. Ostensibly to commemorate the Great Exhibition of a hundred years previously, it was also to express the new feeling of optimism and resolve. And where the first exhibition had left the legacy of the extraordinary Crystal Palace, the Festival left behind the very modern concrete mass of the South Bank Arts complex.

Heathrow airport opened to commercial flights in 1946, and the first double-decker red buses (dubbed the Routemaster) appeared on London roads in 1956. But in the early 1950's there were still elements of London that would have seemed very familiar to any visitors to the original Great Exhibition. For a long time the chimneys of London had been pouring out sulphur dioxide into the atmosphere, and during periods of temperature inversion, these gave rise to fogs, the famous London ‘pea-soupers’.

Things reached a crisis point when London was subjected to a series of dense fogs (nicknamed 'smogs' as they were supposed to be a mixture of smoke and fog) which began to kill a sizeable proportion of its inhabitants. So thick were these fogs that it became virtually impossible to drive, buses needed men with lanterns walking in front of them to guide them and the only way that pedestrians knew there were other people around them was because they could hear them coughing. Towards the end of the fifties the smogs were so bad that thousands of people would die in a single day, usually the very old and the very young.

The Clean Air Act of 1956, forbidding the burning of fuel that was not smokeless, was felt at the time to be authoritative and unfair but, although it took time, it worked. The smogs became a thing of the past, and the London air no longer smelled of soot.

Then in the early 1960's suddenly everybody started wearing colourful and extravagant clothes, and the smog was replace by an an air of hedonism and pleasure. London began to ‘swing’. Carnaby Street, unknown before the sixties, became one of the most famous streets in London, along with the King’s Road, in Chelsea. The Portobello Road street market became a centre of music and fashion and Notting Hill Carnivals began.

London in the sixties had its own unique atmosphere, a heady hallucinogenic gas that induced a feeling of well-being and insensitivity to bright colours. People flooded in and the tourist industry prospered.

The '60's were to see some major changes to London's architecture and skyline too. Tower blocks were erected all over the city, even St Paul’s was concealed in a concrete copse and this tendency reached its height with the infamous Centre Point.

Then in the late 1970's and early 1980's the decline of london's docks started to reverse, with whole complexes of housing and commercial buildings appearing on sites which had been virtually unchanged since the days of Victoria. The most significant of these is the Docklands / Canary Wharf development, with its own light railway.

London is still changing rapidly today. Witness the recently completed Swiss Re building - or "Giant Ghurkhen". It is a more vital, cleaner, and prosperous place than at any time before. But there are still aspects of London which would not seem all that unfamiliar to someone who lived here at the beginning of the century, for example, at night the homeless remain huddled on many of central London's pavements covered by their blankets.

As always, London is a mixture of the good and the bad. For the tourist it is a safe and a fascinating environment - providing a unique historical perspective, mixed with entertainment of the most up-to-date kind. It is a cosmopolitan city with a feeling of optimism and excitement, the hum of history as its background, the clatter of commerce and business in the forefront, changing as it has always done.

Find out about other periods on London's history on our London History page.