From the days of the earliest kings, the defense of Polish soil demanded constant vigilance against Mongol, Tatar, and, later, German encroachment. In the 1400s, the first century of Poland's union with Lithuania, Polish soldiers often battled the Teutonic Knights (see Glossary), who threatened the union from their stronghold along the Baltic seacoast (see The Polish-Lithuanian Union , ch. 1). Poland was regarded as the outer bastion of Western Europe, and the Poles, led by an aristocratic military caste, accepted the mission to defend Western civilization against Eastern intrusions. Jan Sobieski's defeat of the Turks at Vienna in 1683, the last great military victory of the Polish-Lithuanian Commonwealth, was a turning point in the centuries-long struggle against westward expansion of the Ottoman Empire.

By 1725, however, Peter the Great had established a strong, unified Russian Empire that began to compete with the Ottoman Turks for dominance of the Slavic lands between them. At the same time, internal political decay weakened the Polish-Lithuanian Commonwealth, and Poland fell permanently behind Russia as a military power (see Decay of the Commonwealth , ch. 1). In the eighteenth century, Russia assumed the role of protector of Poland, first against Sweden and then against Prussia. In this period, the national army serving the Polish king degenerated from its previously honored position. Manpower and royal prestige dwindled as local landlords raised their own private armies. Under these conditions, Poland lacked the military strength to resist the three partitions imposed by Austria, Prussia, and Russia between 1772 and 1795. The courageous but hopeless campaign of Tadeusz Kosciuszko's insurgent army against the Russian Army in 1794 marked the final chapter in that era of Polish independence. By 1795, Poland had been erased from the map (see The Three Partitions, 1764-95 , ch. 1).

Although the army could not prevent the final partition of the country, its veterans and graduates of the military college fought alongside the armies of Napoleon in his campaigns against Austria, Prussia, and Russia. Many Poles also served in the army of Congress Poland after 1815 (see The Napoleonic Period , ch. 1). Józef Poniatowski, nephew of the last Polish king, distinguished himself in Napoleon's 1809 campaign against Austria. The Polish Legion participated in Napoleon's invasion of Russia in 1812.

In the nineteenth century, Polish soldiers and officers served in the armies of Russia, Prussia (Germany), or Austria, depending on which power occupied their region. In this period, the practices of the partitioning powers exerted great influence on Polish military thought. Poles rose to high command positions, particularly in Austrian service. Poles fought on both sides during W3a6 World War I, and all three occupying powers exerted great efforts to maintain the loyalty of the Poles in their jurisdictions. A Polish army was formed in France to help protect that country from the Central Powers, whereas Józef Pilsudski raised his Polish Legion to fight against Russia (and, more incidentally, for Austria) in the hope of eventually regaining Poland's independence from Russia. Much of the fighting on the eastern front in World War I took place on the territory of the former Polish Republic. Some 2 million Polish soldiers fought with the armies of the three occupying powers, and 450,000 Poles died in the war.

Data as of October 1992