Jan Karski's siblings: Cyprian, Laura and Marian Kozielewscy

Karski’s origins were humble. His father, Stefan Kozielewski, was a leatherworker and craftsman who died when the boy was 6. Karski’s eldest brother, Marian Kozielewski joined Marshall Piłsudski’s Legions and had a hand in Piłsudski’s successful campaign for national independence in 1918 after 130 years of partitions and foreign governance. It was Marian who became a father to the young Karski. Both Karski’s mother Walentyna, and his brother, Marian, instilled in him an idealism prevalent for that generation, where God, Honor and Homeland were perceived as the three pillars on which the Second Republic stood.