Roman, Saxon and Viking London
The Roman town of Londinium was established as a commercial centre around 50CE, adjacent to a bridge across the river Thames that had been constructed by the Roman legions, on a site close to what is now known as "the City". About ten years later it was destroyed by the Icennii, who were a rebellious Norfolk tribe led by Queen Boudicca. After rebuilding, it is believed to have become a garrison town, and around the end of the 2nd century it was fortified by the construction of a massive stone wall about 15 feet high and nearly two miles long (remnants of which still exist). The 7th century Saxon trading centre of Ludenwic was sited to the West of the walled city, and the first Westminster Abbey is believed to have been built there in the 8th century, although the first cathedral church of St Paul is known to have been built within the walled city in the 7th century. The walled city was re-occupied in the 9th century during the rule of Alfred the Great, and London Bridge may have been rebuilt during the reign of Canute. 
1066 Coronation of William the Conqueror in Westminster Abbey.
1078 The White Tower is under construction on the site to be known as the Tower of London[.
1097 Westminster Hall is under construction.
1157 The merchants of the Hanseatic League are granted a Royal licence to operate at its "Steelyard" London trading post
1176 London Bridge is rebuilt in stone.
1348 The Black Death kills two-thirds of the population.
1394 The Mercers Company of cloth traders is granted a Royal Charter to trade in London
Tudor and Stuart London
1514 Docks are under construction at Woolwich and Deptford
1515 Hampton Court Palace is under construction.
1566 The Royal Exchange is under construction as an international trading centre
1599 The Globe Theatre is opened on Bankside.
1621 The second Banqueting House is opened, its predecessor having been destroyed by fire.
1666 The Great Fire of London.
1694 The Bank of England is founded .
1698 Trading in marketable securities at Jonathan's coffee house
The 18th and 19th centuries
1746 The first Westminster Bridge is opened.
1753 The British Museum is founded
1760 The Bow Street Runners are London's first band of Constables
1762 Buckingham House becomes a royal residence.
1773 The London Stock Exchange is established.
1829 London Metropolitan Police is formed
1837 Euston station is opened as the London terminus of the London and Birmingham Railway
1859 London's sewerage system is under construction.
1863 The Metropolitan underground railway begins operating.
1889 The London County Council is established