First partition of Poland

First Partition of Poland
Polish-Lithuanian Commonwealth after the First Partition as protectorate of Russian Empire (1773–1789)
Population losses
To Prussia	580,000
To Austria	2,650,000
To Russia	1,300,000
Teritorial losses
To Prussia	36,000 km²
To Austria	83,000 km²
To Russia	92,000 km²

The First Partition of Poland took place in 1772 as the first of three partitions that ended the existence of the Polish-Lithuanian Commonwealth by 1795. Growth in the Russian Empire's power, threatening the Kingdom of Prussia and the Habsburg Austrian Empire, was the primary motive behind this first partition. Frederick the Great engineered the partition to prevent Austria, jealous of Russian successes against the Ottoman Empire, from going to war. The weakened Commonwealth's land, including what was already controlled by Russia, was apportioned among its more powerful neighbors—Austria, Russia and Prussia—so as to restore the regional balance of power in Central Europe among those three countries. With Poland unable to effectively defend itself, and with foreign troops already inside the country, the Polish parliament (Sejm) ratified the partition in 1773 during the Partition Sejm convened by the three powers.

In the late 17th and early 18th centuries, the Polish-Lithuanian Commonwealth had been reduced from the status of a major European power to that of a Russian protectorate (or vassal or satellite state), with the Russian tsar effectively choosing Polish-Lithuanian monarchs during the free elections and deciding the outcome of much of Poland's internal politics, for example during the Repnin Sejm, named after the Russian ambassador who unofficially presided over the proceedings.

The First Partition occurred after the balance of power in Europe shifted, with Russian victories against the Ottomans in the Russo-Turkish War (1768–1774) strengthening Russia and endangering Habsburg interests in that region (particularly in Moldavia and Wallachia). At that point Habsburg Austria started considering waging war against Russia.