Konstantin Konstantinovich (Xaverevich) Rokossovsky (Polish: Konstanty Ksawerowicz Rokossowski, Russian: Константи́н Константи́нович (Ксаве́рьевич) Рокоссо́вский; December 21 [O.S. December 9] 1896 – August 3, 1968) was a Soviet officer of Polish origin who became Marshal of the Soviet Union, Marshal of Poland and served as Poland's Defence Minister. He was among the most prominent Red Army commanders of World War II, especially renowned for his planning and executing of Operation Bagration, one of the most decisive Red Army successes of the Second World War.
Rokossovsky was born in Warsaw, then part of Congress Poland under Russian rule. His family had moved to Warsaw following the appointment of his father as the inspector of the Warsaw Railways. The Rokossovsky family were members of the Polish nobility, and over generations had produced many cavalry officers. However, Konstantin's father, Ksawery Wojciech Rokossowski, was a railway official in the Russian empire and his Belarusian mother Antonina Ovsyannikova was a teacher (born in Telekhany near Pinsk). Orphaned at 14, Rokossovsky earned a living by working in a stocking factory. In 1911, he became an apprentice stonemason. Much later in his life, the government of People's Republic of Poland used this fact for propaganda, claiming that Rokossovsky had helped to build Warsaw's Poniatowski Bridge. Rokossovsky's patronymic Ksaverovich was Russified on his enlistment into the Russian Army at the start of the First World War to Konstantinovich, which would be easier to pronounce in the 5th Kargopol Dragoon Regiment where he volunteered to serve.