The hall in Monsignor Dillon College in the Plaza Irlanda in Buenos Aires was packed to the doors with more than 600 people who came to hear the Taoiseach. The majority were more comfortable hearing speeches in Spanish. Yet so many faces looked as if they belonged in an Irish club in Kilburn. And when they spoke broken English, the accents of many were unmistakably Irish.
These are Argentina's Irish community, the often forgotten members of the Irish diaspora. Some 400,000 Argentinians are of Irish descent, with many retaining strong attachments to the land of their ancestors.
Many Irish came here in the 18th and 19th centuries, seeking opportunities in a land that held promise, in particular, for those with agricultural skills. It was a destination not only for the unskilled emigrant but also for merchants and professionals who saw better opportunities in the region newly opening up around Buenos Aires.
The fact that their descendants are Spanish speakers and that ties between Ireland and Argentina are so limited serves to isolate them from Ireland.
But when you ask you will be told that their grandparents were Irish, and that they, too, are Irish. The Irish have risen to the highest levels in Argentina's civic and business life. The Taoiseach yesterday met five members of the board of the Banco de la Nacion: one was called McDonagh, another O'Donnell. He also met the acting president of the Argentine Supreme Court, Dr Eduardo Moline O'Connor.
The Irish have their place in Argentine history. Admiral William Brown from Foxford, Co Mayo, founded the Argentine navy. The first recorded Irishman in Argentina was a Father Thomas Fehily, who died in Paraguay in 1625. In the 18th and 19th centuries, many Irish crossed the Atlantic and the equator to settle in Argentina.
President Mary Robinson's visit here in the mid-1990s marked a huge moment in the lives of the Argentinian Irish, who had felt isolated for so long; likewise Mr Ahern's visit. While some at Monsignor Dillon College on Sunday looked Latin, one of the Taoiseach's retinue remarked that many would not look out of place at a Fianna Fail ardfheis.
Many were eager to tell of their Irishness. A young lawyer, Mr Luis Barry, told me of his grandparents who came from Wexford. Ms Clara Furlong's grandfather came to Argentina from Duncormick, Co Wexford, in 1847. Asked if the family's sense of Irishness waned with time, she said her father called Argentinians "bloody natives".
A newspaper for the Irish community, the Southern Cross, was founded by Mgr Patrick Dillon in 1975, while schools for the Irish community have healthy enrolment figures.
Yet some feel a sense of threat to the survival of the Irish identity. Mr Jorge Mackey, president of the Federation of Argentine-Irish Societies, warned of "an unequal struggle to keep our traditions and institutions, and sometimes we are afraid of losing them. Unfortunately our members are being assimilated among other cultures". He insisted this was not chauvinism.
Ireland has long had an embassy here, not only in recognition of the large Irish community but also because of the country's economic importance. Mr Ahern struck an optimistic note regarding the strengthening of links that would ensure the Irish strand in Argentinian culture prospered.
"With not an awful lot of effort," he told reporters, "this can be kept up. The world is a smaller place, and the opportunities here are immense for trade. There is no doubt that the interest is there to do it."