The interwar period was affected by various migration flows, at intrastate level as well as at interstate level. Some of these migrations were voluntary, others were the effect of political events or force. Naturally questions of citizenship and marriage law were linked to these migrations. This paper discusses the consequences concerning citizenship arising out of binational marriages from national and international perspectives. Also, primarily Austrian problems related to citizenship and marriage in the context of migration will be discussed: questions of expulsion, divorce, denationalisation because of political matters and the so called marriages of convenience. Special attention will be paid to relating gender issues.