The Belarusian minority in Poland is composed of 47,000 people according to the Polish census of 2011. This number decreased in the last decades from over 300,000 due to an active process of assimilation. Most of them live in the Podlaskie Voivodeship. A small but unconfirmed Belarusian population remains in the West Pomeranian Voivodeship in western Poland. They may be assimilated into the Polish population, but Belarusian culture has not firmly disappeared in the whole of Poland since World War II. History Polish–Lithuanian Commonwealth Poland first acquired a Ruthenian (predominant ancestors of modern Belarusians) minority in the 16th century, when after the Union of Lublin in 1569 Poland gained control over some of eastern territories formerly belonging to the Grand Duchy of Lithuania. Poland retained control over that region until the partitions of Poland in the late 18th century. In time, the Belarusian culture and nationality started to develop in that region, but also increasing number of people became Polonized. Later influences, particularly Lithuanization and Russification, further contributed to the blurry ethnic border and resulted in a region with many territories with significant minority of one culture or another. 1918–1939 In 1921, at the end of the Polish–Soviet War, Belarusian territories were divided between Second Polish Republic and Soviet Russia under the terms of the Peace of Riga. Thus the newly reborn Poland gained a disputed territory, known as Kresy or West Belarus, inhabited by both Belarusians and Poles. According to the Polish census of 1921, there were around 1 million Belarusians in the country. According to Soviet sources, there were 3 million Belarusians in 1921. Most historians estimate the number of Belarusians in Poland at that time to be from 1.7 million up to 2 million. Belarusians formed 3.1% of the populations of the Second Polish Republic, mostly inhabiting the east-central voivodeships, particularly the Nowogródek Voivodeship. Belarusians consisted the majority of population of Polesie Voivodship, however most of them didn't declare themselves as Belarusians, but at Tutejsi ("Locals"). Several thousand Poles were settled in the area pursuant to the legislation of December 20, 1920. In the elections of November 1922, a Belarusian party (in the Blok Mniejszości Narodowych coalition) obtained 14 seats in the Polish parliament (11 of them in the lower chamber, Sejm). In the spring of 1923, Prime Minister of Poland Władysław Sikorski ordered a report on the situation of the Belarusian minority in Poland. That summer,