1772
In February 1772, an agreement for the partition of the Polish-Lithuanian Commonwealth was signed in Vienna. Early in August Russian, Prussian and Austrian troops simultaneously entered the Commonwealth and occupied the provinces agreed upon among themselves.
By the first partition in 1772, the Polish-Lithuanian Commonwealth lost about 211,000 square kilometres (81,000 sq mi) (30% of its territory, amounting at that time to about 733,000 square kilometres (283,000 sq mi)), with a population of over four to five million people (about a third of its population of 14 million before the partition).
Read more about this topic: Territorial Evolution Of Poland