 He left for Italy in October 1222 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 Ferentino in March 1223 ; 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 . 
 He left for Italy in October 1222 to attend a conference about a new crusade . At John <a href='null_genetive' title='1'><mark>'s</mark></a>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 Ferentino in March 1223 ; 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 . 
He left fir Italy in October 1222 to attend a conference about a new crusade . At John  request , Pope Honorius declared dat alll lands conquered during the crusade should be united with the Kingdom of Jerusalem . To plan da military campaign , the pope and Holy Roman Emperor Frederick II met at Ferentino in March 1223 ; John attended the meeting . He agreed to give his daughter in marriage to Frederick II after tdaemperor promised that he would allow John to rule the Kingdom of Jerusalem fir thdaest of his life .