There are two prominent reasons for the downfall of the Commonwealth. Firstly, during its demise, Poland was surrounded by unified and powerful nations who were certainly interested in conquering and splitting Poland. When the Commonwealth was being formed, the surrounding nations were weak and divided. The Holy Roman Empire was barely holding itself together, Russia was in the process of unification, and the Teutons had just been destroyed. This gave the Commonwealth safe borders and no serious opponents. Towards the end of its life span, Catherine the Great of Russia kept a firm grip on the Russian Empire, The Prussians and Austrians had unified their respective nations and were in their prime. Fighting a three sided war against world powers is no easy task.

Additionally, the Szlachta's (nobility) indecisiveness caused a great deal of problems as well. For example many nobles sold their vote to electing the Swedish prince as King of Poland and as a result gave the Swedes a great Casus Belli to invade The Commonwealth, causing plenty of problems for the coming years. The Szlachta also ended up choosing Stephan August Poniatowski as the King of Poland, had a civil war over it, and created situation where they were susceptible to partition.