During
the Nazi occupation of Poland, a fully operational clandestine Polish
administrative system known as the ‘Underground State’ was established and
conducted its affairs, including an extensive system of undercover education at
the secondary (grammar school) and university levels, as the Nazis had closed
down all education for Poles except for the elementary schools. The ranks of its
armed resistance movement reached over 400 thousand combatants and their
sabotage operations and undercover campaigns were carried out on the largest
scale in occupied Europe. Polish Scouting and Guiding Association played an important role in it, being an underground organisation itself. It conducted military training and sabotage as well as propaganda campaigns.
During the war, there was no collaborationist government in Poland.