 John II even petitioned the Papacy to recognize his claims to Thessaloniki and to the empire, and to help him conquer them.An expedition to "recover" these territories was never organized.The final Palaeologus Marquis, John George, Marquis of Montferrat, died in 1533 and rule of Montferrat was then given to Federico II Gonzaga, Duke of Mantua, by Holy Roman Emperor Charles V. The last female member, Margaret Paleologa, married to Federico II, died in 1566, rendering the Montferrat cadet branch extinct.