Jan Kowalewski

Lt. Col. Jan Kowalewski (23 October 1892 – 31 October 1965) was a Polish cryptologist, intelligence officer, engineer, journalist, military commander, and creator and first head of the Polish Cipher Bureau. He recruited a large staff of cryptologists who broke Soviet military codes and ciphers during the Polish-Soviet War, enabling Poland to weather the war and achieve victory in the 1920 Battle of Warsaw.

Jan Kowalewski was born 1892 in Łódź, Congress Poland, under rule of the Russian Empire. After graduating from a local trade school, between 1909 and 1913 he studied at the University of Liège in Belgium, where he graduated from the faculty of chemistry.

He returned to Poland in 1913, only to be mobilized for the Russian Army the following year, at the outbreak of World War I. He fought in various formations on the Belarusian and Romanian fronts as an officer of the Engineering and Signal Corps, and in December 1918 he was allowed to join the Polish unit formed under command of Gen. Lucjan Żeligowski out of Poles living in Russia. As chief of intelligence of the Polish 4th Rifle Division he crossed the Romanian border with the Division and reached Poland in May 1919.

A polyglot and amateur cryptologist, Kowalewski was initially attached to the staff of Gen. Józef Haller, fighting in Volhynia and Eastern Lesser Poland during the Polish-Ukrainian War for the city of Lwów. During his service there, he managed to break the codes and ciphers of the army of the West Ukrainian People's Republic and General Anton Denikin's White Russian forces. Though his discovery was due to accident and boredom (he had to spend all night segregating radio intercepts and discarding the encrypted ones), it was a major sensation among the staff.

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