Abwehr Major Hermann Joseph Giskes (28 September 1896 – 28 August 1977) was a wartime intelligence operative primarily stationed in the occupied Netherlands, and head of Abwehr Section IIIF. He is best known as one of the leading lights behind the Englandspiel operation. Giskes' activities were responsible for supplying a great deal of disinformation to British intelligence services for much of World War II, and for the arrest of more than 50 Allied agents. Giskes first succeeded in gaining the partial cooperation of captured British agent Hubertus Lauwers, who sent encrypted messages (but missing security checks) back to British SOE at Giskes' direction, under duress. Then dozens of agents parachuted in succession, and were captured by the Germans, along with tons of equipment.
When it became apparent that the penetration had been uncovered, Giskes on 1 April 1944 sent the following message in clear to London (in Marks, p499):
To [the SOE section chiefs] Messrs Blunt,[n 1] Bingham[n 2] and Succs Ltd., London. In the last time you are trying to make business in Netherlands without our assistance stop we think this rather unfair in view of our long and successful co-operation as your sole agents stop but never mind whenever you will come to pay a visit to the Continent you may be assured that you will be received with the same care and result as all those who you sent us before stop so long.
- Leo Marks - the SOE cryptographer largely responsible for uncovering Giskes´ penetration of the Dutch circuit
- Between Silk and Cyanide - Leo Marks' account of wartime cryptography in the SOE
- The Eureka-Rebecca compromises —another look at special operations security during World War II.
- Hastings, Max (2015). The Secret War: Spies, Codes and Guerrillas 1939 -1945 (Paperback). London: William Collins. ISBN 978-0-00-750374-2.
- London Calling North Pole - H.J. Giskes, Bastei Lübbe, Bantam (publ.), 1982, (original publication London ruft Nordpol : das erfolgreiche Funkspiel der deutschen militärischen Abwehr)
- Time Review of London Calling North Pole