Please answer a question about the following article about Westminster Abbey:

Since the coronations in 1066 of both King Harold and William the Conqueror, coronations of English and British monarchs were held in the abbey. In 1216, Henry III was unable to be crowned in London when he first came to the throne, because the French prince Louis had taken control of the city, and so the king was crowned in Gloucester Cathedral. This coronation was deemed by the Pope to be improper, and a further coronation was held in the abbey on 17 May 1220. The Archbishop of Canterbury is the traditional cleric in the coronation ceremony.[citation needed]

Who had taken control of London when Henry III was to be crowned?
French prince Louis