Justinian's rule was not universally popular; early in his reign he nearly lost his throne during the Nika riots, and a conspiracy against the emperor's life by dissatisfied businessmen was discovered as late as 562. Justinian was struck by the plague in the early 540s but recovered. Theodora died in 548 at a relatively young age, possibly of cancer; Justinian outlived her by nearly twenty years. Justinian, who had always had a keen interest in theological matters and actively participated in debates on Christian doctrine, became even more devoted to religion during the later years of his life. When he died on 14 November 565, he left no children. He was succeeded by Justin II, who was the son of his sister Vigilantia and married to Sophia, the niece of Theodora. Justinian's body was entombed in a specially built mausoleum in the Church of the Holy Apostles until it was desecrated and robbed during the pillage of the city in 1204 by the Latin States of the Fourth Crusade.