Government Ministers today travel abroad freely. But the first visit of an Irish prime minister to North America did not take place until 1928, more than five years after the foundation of the State.

The visit was overdue but important, and photographs recently discovered bring it to life. William T Cosgrave went to thank Americans for their support in the struggle for independence, but also to seek investment for Ireland.

Cosgrave especially wanted to convince bondholders of Ireland’s trustworthiness. So he promised to repay them money loaned to the first Dáil during the War of Independence, although the Free State was not legally bound to do so.

Given the condition of Irish finances after the Civil War, Cosgrave’s determination to keep bondholders happy was an uncanny foreshadowing of more recent events.

Great crowds turned out to see him in the US, and 100,000 thronged the streets of Dublin to welcome him home.

Joseph Walshe, secretary of the department of external affairs in Dublin, had strongly urged a visit, not least because the Vatican was milking Irish-Americans for money that the Free State might get instead.

Walshe told the cabinet in 1927: “The pope recently sent a special envoy to New York to marry the daughter of an illiterate Tipperary man who had amassed five million in a little over 20 years. It is well known that this individual and a considerable number of similar types are ready to invest their money in Ireland if given the proper encouragement and publicity.”

Also urging a visit was Timothy Smiddy, an economics professor who had advised Collins and Griffith during the Treaty negotiations. He was Ireland’s urbane man in Washington DC, the first representative abroad of any British dominion.

Smiddy flanked Cosgrave throughout the visit, as did Desmond FitzGerald, then minister for defence.

Their schedule was exhausting. Midwinter storms had meant a miserable January crossing of the Atlantic, and Cosgrave caught a bad cold.

In Manhattan he visited Wall Street and met 200 prominent US business leaders committed to free trade. In Washington he found time to indulge his love of horseriding.

Cosgrave identified as “great moments” of his tour a conversation with President Calvin Coolidge and meetings with members of Congress, where he was warmly welcomed on the floor of each house. He told them that he was returning the visit of Benjamin Franklin to Ireland 150 years earlier. It was said that Cosgrave “laughed heartily during informal conversations in the corridors” of Capitol Hill.

Travelling north through a storm to Canada, Cosgrave and his party narrowly escaped death when his train jumped the tracks in Ontario. The driver was killed and some passengers seriously injured.

Although tired and ill, Cosgrave descended from his carriage and, it was reported, "plodded through snow drifts almost waist deep, going from place to place visiting the injured and inquiring as to their hurts. He then took an active part in the direction of the rescue work and offered his valuable advice." (The Ottawa Evening Citizen's reference to "Pres Cosgrave" reflects his position not, strictly, as taoiseach but as president of the executive council of the Irish Free State.)

Cosgrave and his party were said to have “displayed the utmost solicitude”. He recited Psalm 130 (“De Profundis”) over the white-shrouded body of the driver.

The Canadian prime minister, William Lyon Mackenzie King, found Cosgrave and FitzGerald unnerved by their experience. King wrote in his diary, “Had they been killed it would have been a terrible thing for the Empire. It might have meant De Valera getting ahead . . . ”

In Chicago Cosgrave was feted by the Irish Fellowship Club, which had been founded by the O’Shaughnessy brothers and other prominent Irish-Americans. The organisation was instrumental in persuading him to travel.

Cosgrave looks exhausted in a photograph taken just before he sailed home from New York on February 4th. His doctor had to insist on him leaving his last event, the Emerald Society’s ball at the old Waldorf-Astoria hotel. Newspapers reported that “upwards of seven or eight thousand people had assembled to meet him” and “he was literally ‘mobbed’ by the bankers who wished to shake his hand” .

Although Éamon de Valera was also in New York, and staying at the Waldorf-Astoria, the two men did not grasp this opportunity for a dramatic gesture of reconciliation.

Pressed by reporters, Cosgrave asked, "Should the head of a government visit one of its citizens?" As the New York News noted, "There was a touch of frost in his voice."

Yet the serious and gruelling nature of the trip did not entirely blunt Cosgrave’s sense of humour. It was said that, unwilling to become embroiled in a thorny domestic issue, he had “refused to comment on prohibition”, the US law banning the sale of alcohol between 1919 and 1933. On one occasion, however, he was tempted to quip that prohibition “is not one of Ireland’s many problems”.

Colum Kenny is professor of communications at Dublin City University and author of An Irish-American Odyssey: The Remarkable Rise of the O'Shaughessy Brothers (University of Missouri Press). He will talk about Cosgrave's visit to the US at the American Conference for Irish Studies in Florida on March 26th