Menachem Oren (born Mieczysław Chwojnik; Hebrew: מנחם אורן; 1903 – December 1962)[1][2] was a Polish-born Israeli chess player and mathematician.
Chwojnik was the strongest Cracovian chess player in 1920s, a thrice winner of the Kraków championship (1919, 1925, 1926).
[4] In 1928, he represented Poland on fourth board at the 2nd Chess Olympiad in The Hague (+4 –3 =4), and won the team bronze medal.
During World War II, he lived in the Soviet Union.
In 1949, Chwojnik emigrated, via Czechoslovakia and Austria, to Israel, where he had changed name to Menachem Oren.