sixth crusade(n = noun.act) - a Crusade from 1228 to 1229 led by the Holy Roman Emperor Frederick II who fell ill and was excommunicated by the Pope; by negotiation Frederick II was able to crown himself king of Jerusalem;
is a kind of crusade

crusade, fifth crusade, first crusade, fourth crusade, second crusade, seventh crusade, sixth, sixth baron byron of rochdale, sixth cranial nerve, sixth form, sixth sense, third crusade, youth crusade