Cichociemni were elite special-operations

Special operations

Special operations are military operations that are considered "special" .Special operations are typically performed independently or in conjunction with conventional military operations. The primary goal is to achieve a political or military objective where a conventional force requirement does...

 paratroops of the Polish Home Army (Polish: Cichociemnych Spadochroniarzy A K) of the Polish Army in exile

Polish Armed Forces in the West

Polish Armed Forces in the West refers to the Polish military formations formed to fight alongside the Western Allies against Nazi Germany and its allies...

, created in Great Britain

Great Britain

Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

 during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 to operate in occupied Poland.
The origins of the name are obscure and will never be known but was probably related to how some soldiers would seemingly disappear from their line units overnight to volunteer for special operations service and it also describes those "who appear silently where they are least expected, play havoc with the enemy and disappear whence they came, unnoticed, unseen."

The Cichociemni were trained initially in Scotland in preparation for missions for the Polish underground in occupied Poland such as building clearance and bridge demolition.