Implementation of Green was the responsibility of Generalleutnant Leonhard Kaupitsch Commander of the German Fourth and Seventh Army Corps. Army Group B. The originator of the idea for Green is thought to be newly promoted Field Marshal Feodor von Bock, Army Group B. Bock had operational command for the western flank under Operation Sealion. Once collated, thirty two copies of Green were distributed as "Top Secret" on 8 August 1940 to the German High Command, a number of copies survived World War II. This article needs to be reviewed! Operation Green has to do with Czechslovakia!
"..a landing in Ireland can be attempted only if Ireland requests help. For the present our envoy [assumed to be Dr. Eduard Hempel of the German Legation] must ascertain whether De Valera desires support and whether he wishes to have his military equipment supplemented by captured British war material (guns and ammunition), which could be sent to him in independent ships. Ireland is important to the Commander in Chief, Air, [Göring] as his base for attacks on the north-west ports of Britain, although weather conditions must be investigated. The occupation of Ireland might lead to the end of the war.
The controversial historian David Irving dates Hitler's interest in an invasion of the "Irish Republic" to around mid- to late November 1940, and says he asked his High Command (OKW) to analyze the pros and cons on 27 November. It decided that British naval superiority made such an invasion impossible, and Irving concluded: "Perhaps no episode illustrates so vividly the whims which inspired Hitler's ad hoc military strategy.
"To a defending force, cut off and left to its own devices, the topography of the country [Ireland] does not afford us much protection.. without supplies and reinforcements they would soon feel the increasing pressure of British expeditionary force brought over under the protection of British naval power; sooner or later our own troops would face a situation similar to Namsos or Dunkirk.
In this sense Green can be seen as a worst case scenario for the Oberkommando der Wehrmacht (OKW). While Kaupitsch was to continue planning and training for Sealion/Green he seems to have shelved preparations late 1940 and not returned to them. From his point of view Green had become a feint. This view is reinforced by examining one of the warnings offered to participating German forces in the plan:
"The 'Green' operation confronts us with an entirely new task. Therefore there are no precedents from which we can work. In many cases, troops will have to look after themselves. Each commander must look for a way to achieve his individual objective. Everything depends on the extent of co-operation, on each individual's alertness and ability to take independent action. Confidence in the achievements of German Leadership and the German Soldier should be the foundation of this operation."
The prognosis for German land forces taking part in Green was not good therefore. They had no experience of large scale Amphibious warfare, they may have to fight and survive without resupply, artillery support, screening aerial support, a hostile citizenry. They would have to fight against expected British troop movements from the North of the island and from Britain- invading Ireland to protect their flank. These drawbacks whilst probably acceptable to Hitler were not acceptable to Raeder in his considered estimation four months after the plan was first floated. He did not agree that Ireland could become the "backdoor" into Britain with the present strength of German forces.
As Sealion was rescheduled on 12 October 1940 for the Spring of 1941, then permanently canceled on 13 February 1943, Green became an irrelevance.
Despite the fact that Abwehr intelligence gathering in Ireland had not begun until mid 1939, Green was thorough in detail. This can probably be attributed to the intelligence gathering of German civilians based in Ireland during the 1930s. That the plan for Green was completed days after being ordered is a testament to the planning staff in collating the data. Hitler, arising from his repeated hope of a détente or non-aggression pact of some kind with the British who he considered the "natural allies" of Nazi Germany, had disallowed Abwehr intelligence gathering in Britain during the run up to the war 1936–1938. Even when intelligence gathering was attempted following the capitulation of France it was mostly disastrous—see Operation Lobster I and Operation Seagull (Ireland) series. As Sealion was postponed due to weather and eventually shelved following the launching of Operation Barbarossa, the planning staff working on it issued a total of 2 reprints adding detail as they went.
A second print of the plan in October 1941 added 332 photographs of the Irish countryside and coastline, mostly tourist photos, used to reference highly accurate Ordnance Survey maps. Details on spring tides, geological formations and possible routes German troops could take off projected invasion beaches. Another addendum included in the further reprinting of the plan in 1942 by the OKL, titled "Küsten-Beschreibung des Irischen Freistaates (Irland)" ("Coastal description of the Irish Free State") contained high-altitude aerial photographs of the areas in question, some taken from 30,000 feet, showing houses and trees visible.
Despite this attention to detail and the improvements in volume of data with each reprinting, a lot of the data was however simply out of date or incomplete. For example, the Galway-Clifden railway is described as being operational when it clearly wasn't by the time Green and its reprints were issued. Ireland was also described as perfectly suited to military operations because of its "excellent network of roads" and details on population centres such as Derry and Belfast were accurate but missing details on British troop concentrations housed in the cities. On the other hand, the Ardnacrusha power station on the Shannon was entirely detailed in the plan, thanks to the help of the German firm Siemens, which had built it prior to the war.
In the event of Sealion's success, fulfillment of Green was expected to be the next step, (insofar as operational plans stay static during wartime). No plans for the imposition of government in Ireland, or 'rounding up of dissidents' were included as part of Green however. Dublin was mentioned as one of six German administrative headquarters between the two islands that were to be established on the successful completion of Sealion.
The first landings were to include Artillery and commando squadrons and a motorized infantry battalion. A bridge building battalion was also to be landed along with three anti-aircraft companies and several 'raiding patrols'- to probe Irish Army defenses. Reserves from the German 61st, 72nd, and 290th Divisions were to take up occupation duties in the Gorey-Dungarven bridgehead once it had been established. The overall details for the plan appear to be sketchy from this point onwards, and mostly would have depended on the success or failure of Operation Sealion in Britain.
The landings were to be effected by sea craft available in occupied France at the time, fortunately there were few in existence and Operation Sealion was to have priority- further reasons why Raeder was not happy with Green. Green was expected to utilise over 50,000 German troops and Sealion was expected to use 160,000 but for Green the Germans only found two steamships available around the north-western ports of France- the French Versailles and the German Eule together with three small coasters: Mebillo, Clio and Franzine.
It is also worth pointing out that to get to Ireland the departing ships would have had to circumnavigate the British coastline at Cornwall. Every vessel taking part in Green was to carry anti-aircraft weaponry indicating that the planners expected the Royal Air Force (RAF) to intercept them, although air cover from the Luftwaffe's West of France Air Command was to be provided as part of Sealion.
There were gaps in the German planning, for instance the plans for the proposed incursion of Cobh (as a possible beach-head area in Green) is not accompanied with details of the 9.2 inch and 6 inch artillery defences located there. This weaponry had formed part of the defences of the Treaty Ports which the British had handed over to Irish forces in 1938.
Green dealt only with the plan for invasion, as no details on any subjugation of the population, and eventual conquest of the entire island were included. Among the Irish population however there was a small element of support for the Third Reich due to past British colonial brutality. Sketchiness with regards to the plan has contributed to calls that it was more a diversionary attack than actual attempt to take over the island, although once committed it may have been hard for the German forces to withdraw.