Secret files revealed the Irish Government was swamped by letters of outrage, many from Irish people living overseas, over the decision by Taoiseach Éamon de Valera to visit the German Legation in Dublin to express condolences on the death of Nazi leader Adolf Hitler in May 1945.

The documents have been released as part of the State Papers by the National Archive.

Irish officials also carefully catalogued the reaction across the world media to the Taoiseach’s action.

Mr de Valera called to see the German minister to Ireland, Dr Eduard Hempel, on May 2, 1945, after he had heard of the death of Adolf Hitler.

Surrounded by units of the Red Army in the ruins of Berlin, Hitler had ­taken poison and shot himself on April 30 to prevent being captured alive by the Soviets. His partner, Eva Braun, also took her own life as did several other high-ranking Nazi officials and their families, including propaganda chief Dr Josef Goebbels who died along with his wife Magda and their six children.

The files detailed, in particular, how stunned Irish-Americans were at the decision to express condolences over the death of Hitler.

Ireland’s Washington mission was swamped with queries as to whether the story was true – with others slating the Taoiseach and Ireland for such a move.

One Massachusetts congressman, Henry Shattuck, called for action to be taken against Ireland.

Mr Shattuck, who endowed the chair of Celtic Studies at Harvard University, urged that Ireland should not be allowed to join the United Nations because of what the Taoiseach had done.

Many of the Irish-Americans who contacted the Irish mission were furious because they had friends or relatives serving with US forces fighting the Nazis in Europe.

“I respectfully ask you to close the Irish Legation. It is a standing insult to all of us. You stink, you are swine,” Donegal-born James O’Callaghan wrote.

Detroit Gaelic League secretary Jack O’Loan pleaded for accurate ­information given the fall-out from the move.

“Please give us full facts ­concerning De Valera’s actions on the death of ­Adolf Hitler. Local controversy makes immediate answer imperative,” he said.

Irish-American lawyer Frank Hogan said what the Taoiseach had done was incredibly stupid.

“Every man and woman of Irish blood regrets the stupid action of prime minister (sic) Éamon de Valera of Éire,” he wrote. “Éire had enough of the Sassenach (Saxon) brutality for 700 years of occupation in the Emerald Isle, but you cannot blame all the Irish in the world for the stupidity of one man.”

Edgar Twamley, from Illinois, said Ireland would pay a long-term cost for the mis-step of its leader.

“A more stupid thing for Éire is hard to imagine,” he said.

Another Irish-American, Margaret Mary Turner, said everyone with Irish connections was condemning what De Valera had dared to do.

“We, my people, the Healys, Sullivans and Moynihans and my husband’s folks, the Burneses, would have denounced him (De Valera) with their last breath for daring to call on the German Legation in Ireland and express his sympathy on Hitler’s death,” she wrote.

Such was the outpouring of condemnation that Irish officials in the US briefed Dublin that they were desperately trying to conduct damage control.

In many cases, legation officials tried to correct inaccurate claims about what had happened – and even claims that Ireland had allowed two days of mourning for Hitler or had flown flags at half mast.

Irish Legation official Seán Nunan said many callers were angry and abusive.

“I had three other telephone calls today, two of the people were very ­abusive and on the lines of those reported yesterday,” he noted. “They all claimed to have had relatives killed in this present war.”

Ireland desperately tried to defuse the controversy by sending pro-forma responses to anyone who contacted, explaining that the visit was merely in accordance with diplomatic protocols.

The legation pointed out that Nazi representatives had attended President Franklin Roosevelt’s inauguration in January 1941 even after Germany had overrun the Low Countries and France.