a republic in central Europe, on the Baltic: first united in the 10th century; dissolved after the third partition effected by Austria, Russia, and Prussia in 1795; re-established independence in 1918; invaded by Germany in 1939; ruled by a Communist government from 1947 to 1989, when a multiparty system was introduced; joined the EU in 2004. It consists chiefly of a low undulating plain in the north, rising to a low plateau in the south, with the Sudeten and Carpathian Mountains along the S border. Official language: Polish. Religion: Roman Catholic majority. Currency: złoty. Capital: Warsaw. Pop: 38 170 712 (2017 est). Area: 311 730 sq km (120 359 sq miles)