The White Tower rises in London

After conquering England, William the Conqueror had the White Tower built as a stone keep beside the Thames. It became the core of the Tower of London, which grew into a large fortress.

Sources place the start in the 1070s and say the work took around 20 years. The exact year is uncertain.

Context

Historic Royal Palaces says the Tower was built in the 1070s, shortly after William's victory in 1066 and his coronation, and that the work took around 20 years. William wanted the keep to defend London and to display royal power, dominating the skyline and the attitudes of the defeated Londoners.

The masons brought stone from Caen in France, but most of the labour was done by English workers. A stone keep of this kind was unusual in England at the time, so it signalled the permanence of Norman rule to people who had known only timber and earth defences.

The name comes from a later event. Henry III had the keep painted white in 1240, which is how it became the White Tower. Before that it was simply the great tower of the royal fortress beside the Thames.

Britannica identifies the White Tower as the earliest part of the fortress and dates it only to the 11th century. The wider complex of walls and gates grew over later centuries, and features such as Traitors' Gate date from the 13th century.