'Artur' was a German unrealised plan, schemed in conjunction with a Luftwaffe air bombing campaign over the UK, to support Irish Republican Army activities in Éire, the only neutral British dominion (July 1941).

After 'Seelöwe' and 'Grün' had been placed on hold, 'Artur' was conceived as an attempt to maintain links between the IRA and Germany for future actions against the UK. In July 1940 the German agents Henry Obed, Herbert Tributh and Otto Dietergaertner were landed by small boat at Skibbereen in County Cork in the southern part of Éire. All three had been trained by Oberstleutnant Paul Haehling von Lanzenauer’s Lehr-Regiment 'Brandenburg' zbV 800, the German unit specialising in sabotage and other special forces undertakings behind enemy lines, and their purpose was to make contact with the IRA and to then travel to England to destroy Buckingham Palace with explosives.

Although the three agents were eventually arrested by the Garda Siochána (Irish police) before reaching England, this first phase of the operation revealed to MI5 (the British counter-intelligence and national security organisation) the existence of a larger network of sabotage activities by combined IRA and German interests from Éire, which had declared its neutrality in September 1939.

During August 1940 a campaign to target British interests in Ireland had been conceived by Séan Russell, the IRA’s chief-of-staff, and presented to the German foreign minister, Joachim Ribbentrop, and the head of the Abwehr, Admiral Wilhelm Canaris. Russell requested explosives, guns and radio equipment for use in a campaign to begin during November 1940. Russell, who had been out of Éire before the war to avoid arrest, was to have returned to the Éire in U-65, departing from Wilhelmshaven and landing the IRA man at Smerwick Harbour, County Kerry, on 8 August 1940. Russell died on 14 August before this plan could be implemented, however, and the plan was left to another IRA operative, Frank Ryan, who decided not to return to Éire but instead co-ordinate the bombing campaign from Germany.

In September 1940 Francis Stuart, an IRA spokesman, started to make propaganda broadcasts from Berlin, these calling for the liberation of Northern Ireland from the British, paving the way for the establishment of a unified Irish nation extending over the whole of Ireland.

'Artur' received a major setback, however, when Éire’s government passed the Emergency Powers Act, resulting in the arrest of more than 600 members of the IRA and the capture of Major Hermann Görtz, who had been parachuted into Éire during May 1940 to assist the IRA in preparations for 'Grün'.

Unable to mount an effective ground bombing campaign, the IRA’s focus perforce turned to intelligence gathering. During 1941, information on shipyard and aircraft activity in Northern Ireland were gathered by IRA men and passed to an SS officer named Henning Thompson, who was based in Dublin, for onward transmission to the Abwehr. During a four-week bombing campaign by the Luftwaffe from April 1941, targets in Belfast and Londonderry were hit, resulting in damage to shipbuilding yards, airfields and industries, and in the deaths of more than 800 people. After Germany’s disaster at Stalingrad in the first weeks of 1943, an invasion of Éire was no longer considered a serious possibility. Ryan played no major part in the war from that time on, and died in Dresden during 1944.