Invasion of Northern Ireland

Invasion of Northern Ireland
Part of World War II
Irish Soldiers hand rifles to Nationalist guerillas outside of Belfast, 1945
Date	1943 - 1945
Place	Great Britain
Result	Irish Victory Part of Northern Ireland incorporated directly into Ireland Northern Counties Special Zone formed
Belligerents
Ireland Germany United Kingdom
Leaders
Eamon D'Valera Winston Churchill

The Invasion of Northern Ireland was the invasion of Northern Ireland by the Republic of Ireland against the United Kingdom of Great Britain and Northern Ireland (not to be confused with the post-war United Kingdom of Great Britain) during the Second World War.

The invasion, although inflicting significant losses to the ill-prepared and underequipped Irish Army, ultimately succeeded after two years of continued operations. The invasion was greatly supported by the German Reich due to the military plan of utilizing the ports of Ireland to cut off Britain from any supplies transported via sea, essentially starving out the British in a naval blockade.

With the majority of the British fleet stuck in the Mediterrean and a jumping off point from the Irish island, Operation Sealion was greenlit to proceed, resulting in the invasion of the British Home Islands, and the subsequent end of the European Theatre of the Second World War.

Amongst historians and analysts, the invasion of Northern Ireland is widely regarded as being the penultimate nail in the coffin of the Allied war effort.

Background

Ireland's Position

After the Irish War of Independence and the subsequent Anglo-Irish Treaty of 1921, Ireland was allowed to exist as a Dominion of the British Crown, whilst Northern Ireland opted to stay out from the newly created Irish Free State.

Despite this, many members of the former Irish Republican Army felt slighted by the Treaty, as they had left the 6 Counties in Northern Ireland in English Hands, of which 2 contained a significant Catholic minority, specifically, Fermanagh and Tyrone. These resulted in an uptick of sectarian violence, and a resurgence of violence within Ulster, with many seeing it as Irish land still under British rule.

Besides this, Ireland was still nominally a Dominion of the British Empire and a member of the Commonwealth. The nation had gained de facto independence from Britain after the Irish War of Independence, and the Anglo-Irish Treaty of 1921 declared Ireland to be a "sovereign, independent, democratic state", with the Irish Government adopting a new constitution in 1937

Furthermore, The Statute of Westminster of 1931 meant that unlike in World War I, Britain's entry into the war no longer automatically included its dominions. Thus, in 1939 the Irish Free State had the option of remaining neutral.

Diplomatically, relations between Ireland and Britain had been strained for many years; until 1938, for example, the two states had engaged in the Anglo-Irish Trade War. Nevertheless, Ireland did not sever its vestigial connection with the Crown, most notably being King George VI's few remaining powers within the Irish state, however the 1937 Constitution had provided that the holder of the new office of President of Ireland was in "Supreme Command" of the Defence Forces.

Leadup to War

In the six months prior to the onset of the Second World War, there had been an escalation of Irish Republican Army violence and a bombing campaign in Britain under the new leadership of Seán Russell. De Valera, who had tolerated the IRA as recently as 1936, responded with the Offences against the State Act, 1939. Upon the outbreak of the main conflict in September, subversive activity was regarded as endangering the security of the state. There were fears that the United Kingdom, eager to secure Irish ports for their air and naval forces, might use the attacks as a pretext for an invasion of Ireland and a forcible seizure of the assets in question. Furthermore, the possibility that the IRA (in line with the Irish republican tradition of courting allies in Europe) might link up with German agents, thereby compromising Irish non-involvement, was considered.

This threat was real though, as Russell in May 1940, travelled to Berlin in an effort to obtain arms and support for the IRA. He received training in German ordnance, but died on a submarine while returning to Ireland as part of Operation Dove. A small number of inadequately prepared German agents were sent to Ireland, but those who did arrive were quickly picked up by the Directorate of Military Intelligence. Active republicans were interned at the Curragh or given prison sentences: six men were hanged under newly legislated acts of treason and three more died on hunger strike. The Germans also later came to realise they had overestimated the abilities of the IRA. By 1943, the IRA had all but ceased to exist. In Ireland, neutrality was popular, despite rationing and economic pressure.