The total area of Poland is 312,679 square kilometres (120,726 sq mi), the 8th most populous country in Europe and the sixth most populous member of the European Union, as well as the most populous post-communist member of the European Union.Poland is a unitary state divided into 16 administrative subdivisions, and its capital and largest city is Warsaw.
The bulk of the population converted in the course of the next few centuries.
In 1000, Boleslaw the Brave, continuing the policy of his father Mieszko, held a Congress of Gniezno and created the metropolis of Gniezno and the dioceses of Kraków, Kołobrzeg, and Wrocław.
Once a leading European power with a uniquely progressive political system, the Commonwealth ceased to exist as an independent state, following several territorial partitions among Prussia, the Russian Empire, and Austria from 1772 to 1795.
Poland regained its independence in 1918 at the end of World War I, reconstituting much of its historical territory as the Second Polish Republic.
Since the beginning of the transition to a primarily market-based economy that took place in the early 1990s, Poland has achieved a "very high" ranking on the Human Development Index, The origin of the name Poland derives from a West Slavic tribe of Polans (Polanie) that inhabited the Warta River basin of the historic Greater Poland region in the 8th century.