The"German Plot" was a spuriousconspiracy that theDublin Castle administration in Ireland claimed existed betweenthe Sinn Féin movement and theGerman Empire in May 1918. Allegedly, the two factions conspired to start an armed insurrection inIreland duringWorld War I, which would have divertedthe British war effort. The administration used these claims to justify theinternment of Sinn Féin leaders, who were actively opposingattempts to introduce conscription in Ireland.
The "plot" originated on 12 April when the British arrested Joseph Dowling after he was put ashore inCounty Clare by aGerman U-boat.[1] Dowling had been a member of theIrish Brigade, one of several schemes byRoger Casement to get German assistance for the 1916Easter Rising.[1] Dowling now claimed that the Germans were planning a military expedition to Ireland.[1]William Reginald Hall andBasil Thomson believed him and convinced the authorities to intern all Sinn Féin leaders.[1] 150 were arrested on the night of 17–18 May and taken to prisons in England.[1] The introduction of internment and conscription reflected a decision of theBritish cabinet to take a harder line on theIrish Question following the failure of theIrish Convention.[2]
Paul McMahon characterises the "Plot" as "a striking illustration of the apparent manipulation of intelligence in order to prod the Irish authorities into more forceful action".[1] Republicans were tipped off about the impending arrests, allowing some to escape capture while others chose to be taken in order to secure a propaganda victory.[1] The internment was counterproductive for the British, imprisoning the more accommodating Sinn Féin leadership while failing to capture members of theIrish Republican Brotherhood more committed tophysical force republicanism.[3] This allowedMichael Collins to consolidate his control of the organisation and put it on a more focused military footing.[4]
Even at the time, the proposition that the Sinn Féin leadership were directly planning with the German authorities to open another military front in Ireland was largely seen as spurious.[5] Irish nationalists generally view the "German Plot" not as anintelligence failure but as ablack propaganda project to discredit the Sinn Féin movement, particularly to an uninformed public in theUnited States.[6][7] Historian Paul McMahon comments that this belief is mistaken, and that the authorities acted honestly but on the basis of faulty intelligence.[1] It is still a matter of study and conjecture what impact it had on US foreign policy regarding the 1919 bid forinternational recognition of the Irish Republic.[8]