Tower of London

Victorious at the Battle of Hastings on 14 October 1066, the invading Duke of Normandy, William the Conqueror, spent the rest of the year securing his holdings by fortifying key positions. He founded several castles along the way, but took a circuitous route toward London; only when he reached Canterbury did he turn towards England's largest city. As the fortified bridge into London was held by Saxon troops, he decided instead to ravage Southwark before continuing his journey around southern England.

Most of the early Norman castles were built from timber, but by the end of the 11th century a few, including the Tower of London, had been renovated or replaced with stone. Work on the White Tower – which gives the whole castle its name – is usually considered to have begun in 1078, however the exact date is uncertain. William made Gundulf, Bishop of Rochester, responsible for its construction, although it may not have been completed until after William's death in 1087. The White Tower is the earliest stone keep in England, and was the strongest point of the early castle.

During Edward II's reign (1307–1327) there was relatively little activity at the Tower of London. However, it was during this period that the Privy Wardrobe was founded. The institution was based at the Tower and responsible for organising the state's arms. In 1321, Margaret de Clare, Baroness Badlesmere became the first woman imprisoned in the Tower of London after she refused Queen Isabella admittance to Leeds Castle and ordered her archers to target Isabella, killing six of the royal escort. Generally reserved for high-ranking inmates, the Tower was the most important royal prison in the country.