The Polish Underground State was a secret network of underground military and civilian resistance organizations, united in their support for the exiled Polish government and their opposition to foreign tyranny.
Established during the final stages of the German invasion (September 1939) the Underground State waged a subversive campaign against Nazi then Soviet rule.
The Underground State enjoyed broad popular support during World War Two, but its support splintered throughout the Soviet backed communist takeover. Abandoned by the Allies and deprived of key leaders – who either defected or were exterminated – many of the State’s key institutions dissolved themselves.
However the State as a whole survived two illegal occupations, from 1939 to 1990. Attempts to destroy the network only hardened the resolve and tacit support of millions of Poles to what they saw as the legitimate government under Polish law.