UNDERGROUND RESISTANCE

''For the music community and record label, see Underground Resistance.''
The 'underground' is a nickname used for some resistance movements. "The underground" is also a common name for World War II resistance movements. By extension, the term was also applied to counter-cultural movements, many of which sprang up during the 1960s. In a similar sense, the Underground Railroad was a secretive United States anti-slavery movement which helped slaves to escape repression by providing them with hiding-places and assistance in their attempts to reach freedom in Canada.
In any war, there was some sort of secret military service running behind enemy lines, or away from the view of the general public. These movements were often referred to as underground movements.