 He left for Italy in October <unk> to attend a conference about a new crusade . At John 's request , Pope Honorius declared that all lands conquered during the crusade should be united with the Kingdom of Jerusalem . To plan the military campaign , the pope and Holy Roman Emperor Frederick II met at <unk> in March <unk> ; John attended the meeting . He agreed to give his daughter in marriage to Frederick II after the emperor promised that he would allow John to rule the Kingdom of Jerusalem for the rest of his life . 
