The Romans founded the settlement then called Londinium. 

London was set on fire by Boadicea (also known as Boudicca, a Roman Queen of the region of England now known as Norfolk and Suffolk).

William the Conqueror was crowned in Westminster Abbey.  William the Conqueror was considered to be one of the first "modern" kings, who actually cared about the people who served him.

Completion of the White Tower (the original tower) of the Tower of London.

The first mayor of London was established.

London Bridge completed.

The first English Parliament was established.

Start of the Black Death, which killed around 60,000 people in London.

Caxton build the first printing press at Westminster

St James' Palace built by Henry VIII

The year of Guy Fawkes's gunpowder plot and the attempt to blow up Parliament.  I wonder how life would be different in the UK now if Fawkes had succeeded in his plot!

The Great Plague kills around 100,000 people in London.

St Paul's Cathedral rebuilt by Christopher Wren.  1666 was also the year of the Great Fire of London, in which over 13,000 buildings were destroyed, but comparatively few people died.

A winter Frost Fair is held on the River Thames, during a particularly cold spell that saw the River Thames freeze over.  (At this time, the world was experiencing a particularly cold spell known as the Little Ice Age).

Westminster Bridge completed.

Regent's Park, Regent Street and The Mall (the road that runs from Trafalgar Square to Buckingham Palace) are conceived by John Nash.

The first London police force was established.  Also the first London bus, pulled by a horse!

The opening of London's first railway line, running from London Bridge to Greenwich.

Queen Victoria becomes the first monarch to use Buckingham Palace as an official royal residence.

Nelson's Column erected, in Trafalgar Square.

The Great Exhibition takes place in Hyde Park.  The aim of the Exhibition was to demonstrate the "point of development at which mankind has arrived ...", as stated by Prince Albert, Queen Victoria's husband.

The opening of London's first underground railway.

Houses of Parliament completed.

Tower Bridge completed.

World War 1.  Zeppelin airships are the main threat to London and her people.

World War 2, during which much of the city of London was destroyed during the Blitz.  Many kids were evacuated from London (and other cities in the UK) to countryside location, to avoid the worst effect of the war.

The 14th Olympic Games are held in London.  These Olympics were the first to be televised.

The year of the festival of Britain, a national exhibition that took place on London's South Bank.

The year of the Great London Smog.  Many cities in the UK were afflicted by smog around this time, illustrating just how polluting industry could be at that time.  Sometimes, visibility was reduced to near zero, and respiratory illnesses were numerous.

London is the centre of the "Swinging Sixties", with the King's Road and Carnaby Street being the centres of all the action.

The Greater London Council is abolished, following 21 years of ruling Greater London and various clashes with Government in Parliament.

Canary Wharf, London's tallest building, is completed in the Docklands area of London.  The building is 800 feet high, and - interestingly - was designed by the same architect who designed the World Trade Centre.

The Channel Tunnel opens, linking London Waterloo railways station with the centres of Paris and Brussels.  The London end of the journey is now at St Pancras station.

The Millennium Dome opens in anticipation of the new millennium, and has a very short life-span as very few people show any interest.  The Greater London Authority is established, with left-wing Ken Livingstone elected as Mayor of London.

London wins its bid for the 2012 Olympics.  Terrorist attacks on 7th July on the Underground and a bus leave over 50 people dead and many more injured.  Police shoot Jean Charles de Meneses, believing that he was about to detonate a bomb.

The leadership of London changes from left-wing Ken Livingston to right-wing Boris Johnson.  Time will tell as to what this portends for the future of London!  Financial crises in the City leave people wondering about the future of their investments.  Many blame City bankers for the crisis.