His first international tournament in 1910 was a failure, but he started extensive training and already in 1912 he participated for Russia in the individual jumping competition at the 1912 Summer Olympics in Stockholm.

[4] In 1914 he started service in the Kalisz-based 14th Little Russian Dragoon Regiment, in the rank of Captain of cavalry (rotmistr).

[5] On 15 August 1919 he joined the newly-formed Polish Army in the rank of Major and then Lieutenant Colonel (podpułkownik).

He was withdrawn from front-line service and became a cavalry instructor at various military colleges in Przemyśl, Stara Wieś and Grudziądz.

He also participated in numerous international games, winning World Cup three times: in 1925, 1927 (New York City and 1928 (Nice).

Arrested during the AB Action, he was imprisoned and spent the remainder of the war in German concentration camps of Dachau and Mauthausen-Gusen.

He also served as a horsemanship consultant in various films (and had a cameo appearance in 1959 Lotna by Andrzej Wajda and 1960 The Knights of the Cross by Aleksander Ford).

Although the Rummel family felt Polish and spoke Polish at home,[5] they were in fact heirs to one of the oldest German families in Central Europe, tracing its roots to certain Matthias Heinrich Freiherr von Rummel, a Livonian Brother of the Sword who in 1332 owned the Getzingen castle near Jülich in Westphalia and settled in Courland to support the Teutonic Knights in their struggle against the pagan Balts.