What was the Partition of Poland? Explain.

The Partitions of Poland were three partitions of the Polish–Lithuanian Commonwealth that took place toward the end of the 18th century and ended the existence of the state, resulting in the elimination of sovereign Poland and Lithuania for 123 years. The partitions were conducted by the Habsburg Monarchy, the Kingdom of Prussia, and the Russian Empire, which divided up the Commonwealth lands among themselves progressively in the process of territorial seizures and annexations.

The First Partition of Poland was decided on August 5, 1772. Two decades later, Russian and Prussian troops entered the Commonwealth again and the Second Partition was signed on January 23, 1793. Austria did not participate in the Second Partition. The Third Partition of Poland took place on October 24, 1795, in reaction to the unsuccessful Polish Kościuszko Uprising the previous year. With this partition, the Commonwealth ceased to exist.

In English, the term "Partitions of Poland" is sometimes used geographically as toponymy, to mean the three parts that the partitioning powers divided the Commonwealth into, namely: the Austrian Partition, the Prussian Partition and the Russian Partition. In Polish, there are two separate words for the two meanings. The consecutive acts of dividing and annexation of Poland are referred to as rozbiór (plural: rozbiory), while the term zabór (pl. zabory) means each part of the Commonwealth annexed in 1772–95 becoming part of Imperial Russia, Prussia, or Austria. Following the Congress of Vienna in 1815, the borders of the three partitioned sectors were redrawn; the Austrians established Galicia in the Austrian partition, whereas the Russians gained Warsaw from Prussia and formed an autonomous polity of Congress Poland in the Russian partition.

In Polish historiography, the term "Fourth Partition of Poland" has also been used, in reference to any subsequent annexation of Polish lands by foreign invaders. Depending on source and historical period, this could mean the events of 1815, or 1832 and 1846, or 1939. The term "Fourth Partition" in a temporal sense can also mean the diaspora communities that played an important political role in re-establishing the Polish sovereign state after 1918.

With regard to population, in the First Partition, Poland lost over four to five million citizens (about a third of its population of 14 million before the partitions). Only about 4 million people remained in Poland after the Second Partition which makes for a loss of another third of its original population, about a half of the remaining population. By the Third Partition, Prussia ended up with about 23% of the Commonwealth's population, Austria with 32%, and Russia with 45%.

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(Wandycz also offers slightly different total annexed territory estimates, with 18% for Austria, 20% for Prussia and 62% for Russia.)

During the Napoleonic Wars and in their immediate aftermath the borders between partitioning powers shifted several times, changing the numbers seen in the preceding table. Ultimately, Russia ended up with most of the Polish core at the expense of Prussia and Austria. Following the Congress of Vienna, Russia controlled 82% of the pre-1772 Commonwealth's territory (this includes its puppet state of Congress Poland), Austria 11%, and Prussia 7%.[

The King of Poland, Stanisław August Poniatowski, under Russian military escort left for Grodno where he abdicated on November 25, 1795; next he left for Saint Petersburg, Russia, where he would spend his remaining days. This act ensured that Russia would be seen as the most important of the partitioning powers.

I'll go with that