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Events on Saturday 18 September 1773 1
1773Partition Sejm ratifies the First Partition of PolandPolish-Lithuanian Commonwealth formally cedes territory to Russia, Prussia, and AustriaUnder pressure from occupying troops, the Polish Sejm ratified the treaties ceding roughly 30 percent of the Commonwealth's territory to Russia, Prussia, and Austria, formalizing the partition carried out the previous year. The session became known as the Partition Sejm. It marked the beginning of the dismemberment of the Polish-Lithuanian state, completed by 1795.