In 1910, he joined Combat Organization of the Polish Socialist Party, he was also a member of the Union of Active Struggle and Riflemen's Association.

In 1914, Boncza-Uzdowski joined Polish Legions in World War I, and after the Oath crisis of 1917, he was imprisoned in Beniaminow.

5 p.m., Boncza-Uzdowski appointed his deputy, Colonel Stefan Broniowski, new commander of the two divisions, and together with his chief of staff Albin Habina, and operational officer Jan Rzezniowiecki, left his headquarters, allegedly in search of General Juliusz Rómmel.

On his way towards Gora Kalwaria, Boncza-Uzdowski entered the territory controlled by the Wehrmacht (in the night of September 8/9, near Mszczonow).

In April 1945, Juliusz Rómmel wrote in Murnau that he was a "worthless individual, without any commanding skills, and unfit for the military".