The Polish-Lithuanian and Prussian Alliance was a mutual defense alliance signed on 29 March 1790 in Warsaw between representatives of the Polish–Lithuanian Commonwealth and the Kingdom of Prussia. It was signed in the brief period when Prussia was seeking an ally against either Austria or Russia, and the Commonwealth was seeking guarantees that it would be able to carry out significant governmental reforms without foreign intervention. From the beginning, the alliance was much more valuable to the Commonwealth than to Prussia. Soon after the treaty was signed, the international situation, and changes within the Commonwealth, made the treaty much less valuable to the Prussian side. Meanwhile, the Commonwealth embarked on a series of major internal reforms, seeing the alliance as a guarantee that it had the backing of a powerful neighbour in the process, but in fact, Prussia felt that those reforms were not in its best interest and felt threatened by them. When Russia invaded the Commonwealth in May 1792, Prussia refused a request to honour the alliance and intervene, arguing that it was not consulted with regard to the 3 May Constitution, which invalidated the alliance. A few months later, in 1793, Prussia aided Russia in the suppression of the Kościuszko Uprising. Background The Polish–Lithuanian Commonwealth (also known as the Poland) had been a major European power since its formation in the late 16th century and was still one of the largest states in Europe in the latter part of the 18th century. Over time, its state machinery had become increasingly dysfunctional. By the early 17th century, the magnates of Poland and Lithuania controlled the state or rather managed to ensure that no reforms would be carried out that might weaken their privileged status (the so-called "Golden Freedoms"). Tentative reforms began in the late 18th century; however, any idea of reforming the Commonwealth was viewed with suspicion not only by its magnates but also by neighbouring countries, which were content with the state of the Commonwealth's affairs and abhorred the thought of a resurgent and democratic power on their borders. With an army numbering around only 16,000, Poland found that its neighbours could easily intervene directly: the Imperial Russian Army numbered 300,000, the Prussian Army and the Imperial Austrian Army 200,000. All of those powers had already annexed about a third of the Commonwealth territory and population ( and four to five million people) in the First Partition