almohad dynasty archbishopric of riga battle of grunwald biskupiec braniewo christian of oliva diocese duchy of prussia east prussia east prussian plebiscite erich mendelsohn ethnic germans ethnic cleansing evacuation of east prussia feliks nowowiejski first partition of poland folk etymology frombork german empire german language germans golden bull of rimini high prussian history of poland holy roman empire hugo haase ignacy krasicki italians jingoism jogaila johann friedrich endersch kingdom of prussia konrad i of masovia latin latvian language livonia low prussian lucas watzenrode the younger lusatian culture lutheranism masuria matthias corvinus of hungary maximilian kaller middle ages nicolaus copernicus northern crusades old prussians olsztyn papal legate poland polish language pomerania pope gregory ix pope innocent iii pope pius ii potsdam conference prince-bishop prussia rainer barzel regina protmann reszel royal prussia sambia sejmik senate spain teutonic knights union of lublin war of the priests warmiak warmian-masurian voivodeship warmians william of modena world war i world war ii