In the early 13th Century Geoffrey Fitzpiers, Earl of Essex, built a fortified manor house on the site of the present castle, although nothing of this early building has survived. The Castle changed hands several times, and in the mid-15th century extensive building work on the inner courtyard was carried out for Ann Stafford, widow of the Duke of Buckingham. By the 1520s the Castle belonged to the Wingfield family, who had it rebuilt as a Tudor manor house. Parts of this building can still be seen, behind a glass panel in the wall of the Red Room and especially in the corridor near the Chapel. Catherine of Aragon is said to have spent the last two years of her life at Kimbolton, where she led an austere religious life until her death there on 7th January 1536, either from cancer or by poisoning. A large portion of the South Wing collapsed in 1707 but the Queen's Chamber remained intact, and it is to this Chamber that the lonely Queen returns, robed in a white dress and wearing her crown. Another ghost of Kimbolton Castle is that of Sir John Popham, Lord Chief Justice during the reign of Elizabeth I, who lies in wait for poachers in the park, just as he had done in life. He has also been seen on many occasions sitting on a wall, ready to pounce on any intruder. A third ghost is that of an unidentified child, who was flung from one of the castle's windows many years ago, to meet a dreadful death on the flagstones below.