In 1918, after 123 years of partition, Poland regained its independence. The immediate military task was forming a new national army from soldiers and officers who had fought on both sides--although officers who had served on the side of the Central Powers dominated the new army. In the territorial uncertainty that followed the war, the Red Army pushed westward, aiming to use Poland as a bridge over which to spread socialism into postwar Germany. Pilsudski blocked this advance in 1919 then in 1920 he advanced eastward with the goal of including Ukrainian and Belorussian territory in a new Slavic state. Polish forces were thrown back nearly to Warsaw, where Pilsudski defeated the Soviets and began an effective counterattack that preserved Poland's independence from Soviet domination in the interwar period.

Pilsudski's military and political prominence ensured that the armed forces became an important national institution in the new government. Many Poles saw the army as both the symbol and the guarantor of their country's independence and unity. In 1926, after Poland had experienced several years of political uncertainty and weak leadership, Pilsudski took over the state in a military coup, assuming the posts of minister of defense and general inspector of the army. In the interwar period, military officers held prominent positions in the national government, and their elevated status fostered intense political and personal rivalries as well as high-level corruption. After Pilsudski's death in 1935, Poland was ruled ineffectually by a group of his former subordinates, who remained in power until 1939.

After World War I, Polish national security rested on a military alliance with France, which guaranteed Poland's independence and territorial integrity. Poland was unsuccessful in joining the Little Entente, a French-sponsored alliance of Czechoslovakia, Romania, and Yugoslavia, because Czechoslovakia suspected Polish territorial ambitions along their mutual border. In protecting its sovereignty during this period, Poland had as its primary concerns maintaining a balance between its two powerful neighbors, Germany and the Soviet Union, and avoiding a situation where the two would take concerted action against Poland and divide it once again.

Data as of October 1992