During the invasion of Poland of 1939 he commanded the Czersk Operational Group and was among the highest ranking Polish officers to be killed in action in that war.

There he formed a unit of the Związek Strzelecki and started organizing military training for the Polish emigrees and students.

It was then he adopted his nom de guerre of Grzmot (Polish language for thunder), which later formed a part of his surname.

In August 1914 he became the member of The Seven Lancers of Belina under Władysław Belina-Prażmowski, the first detachment of the Polish Cavalry to cross the border with Privislinsky Krai.

At the start of the invasion of Poland in 1939, he commanded his unit as the core of the Czersk Operational Group which was to shield the Vistula river crossings against the German offensive and to protect the flanks of the Pomorze Army.