austrian silesia bohemia carpathian mountains cieszyn silesia cieszyn silesian dialect czech republic czech lands czech language czechoslovakia ethnologue expulsion of germans after world war ii german language habsburg monarchy helen zelezny-scholz ivan lendl johann palisa kingdom of prussia lower silesia moravia moravian-silesian region munich agreement nazi germany olomouc region olza river opava opava river ostrava poland polish language polish minority in the czech republic province of silesia regions of the czech republic reichsgau silesia slavic peoples slovakia sudetenland sudetes treaty of versailles zaolzie