Following the death of Andronikos III in 1341 another civil war broke out, lasting until 1347. Andronikos III left his six-year-old son under the regency of Anne of Savoy. The de facto leader of the Byzantine Empire, John Cantacuzenus, was not only a close associate of the deceased emperor but an extremely wealthy landowner, and he wanted to become regent instead. He was unsuccessful, but he was declared emperor in Thrace. More or less this conflict was class warfare, with the wealthy and powerful supporting Cantacuzenus and the poorer supporting the empress regent. In fact when aristocrats in 1342 proposed that the city of Thessalonica be turned over to Cantacuzenus, anti-aristocrats seized the city and governed it until 1350.