He was born Kazimierz Łukoski in 1890, in the village of Sokół near Garwolin, in the Siedlce Governorate of the Russian Empire (in the Masovian Voivodeship of present-day Poland).

During his studies in the capital of Austria-Hungary, he became involved in the Drużyny Strzeleckie para-military organization and adopted the nom de guerre of Orlik (Polish for lesser spotted eagle), which later formed a part of his surname.

As part of the Józef Haller's Blue Army, in March 1919 Kazimierz Łukoski left Odessa for France, where he became the commander of the Polish 48th Infantry Regiment, with which he returned to Poland.

Shortly before the cease-fire he became the commanding officer of the 22nd Brigade, after which he was attached to the Polish 12th Infantry Division stationed in Tarnopol (modern Ternopil, Ukraine).

Between 1929 and 1930 he received military training at the Ecole Superieure de Guerre in Paris and the Higher War School in Warsaw, and then returned to his previous post in the 11th Division.