Hungary

After the collapse of Austria-Hungary in 1918, Hungary briefly became a republic and then a Soviet republic before becoming the Kingdom of Hungary (without a king) under Regent Miklós Horthy from 1920. Vastly reduced by the Treaty of Trianon (losing 2/3 of its territory), it allied with Nazi Germany in WWII and was occupied by Soviet forces in 1944–1945. Post-war Hungary became a communist People's Republic until 1989.

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