Michał Zieliński was born on 15th September 1905 in Jarosław. When he was a child, he experienced a personal tragedy because of his father’s death. Consequently, Michał was raised only by his mother, who did everything she could so that her child could get the best education. The difficult family situation and a need to take a job speeded up his maturing process.
The father of Michał Zieliński, Jędrzej, was a small holder, mercenary carter. The mother of Michał Zieliński, Rozalia, came from the famous family of Tokarzowie.