Polish insurgency
The Polish insurgency is an ongoing civil conflict between the resistance fighters of the Polish Underground State, and the Greater Germanic Reich and the General Governorate of the Vistula. The Ukrainian Insurgent Army also fights both the Underground State and the Reich in their quest for an independent Ukraine.
History
Early years
Following the swift collapse of the Polish military, the country was occupied by the brutal General Government. Almost immediately, citizens began launching acts of resistance, and before long the Polish Underground State was formed to counter the Nazi tyranny.
The insurgency
The Polish Underground has been able to survive and thrive in no small part due to the incompetency of Hans Frank. The governor routinely sends reports of Poland being majority German and that the underground is long gone. This means that the Reich is unlikely to reinforce the GG, and Hans Frank is reluctant to tell the truth and most likely lose his position due to incompetence.
In-game
Although the insurgency has been going on for a long time, it will not have any notable presence in the game until after the outbreak of the German Civil War; after the outbreak of said war, the Polish Underground will lead a massive rebellion, outright declaring war on the General Governorate (similar to Her Majesty's Most Loyal Resistance in the British Civil War). They are guaranteed to win, regardless of who was chosen as Hitler's successor (although who was chosen will determine how the country is dealt with after they are victorious in the civil war).