She never let them in
Deasy's boast that Ireland "has the honour of being the only country which never persecuted the jews" is absurd, considering that he himself engages in the kind of hate speech that lays the basis for persecution. It is also untrue: Jews were intermittently persecuted in Limerick in the late 19th and early 20th centuries. His misstatements are crowned by the false assertion that "she never let them in." But all of this falsehood is complicated by the fact that the great Daniel O'Connell made the same boast (in a very different spirit) in the mid-19th century.
Although Jewish history in Ireland goes back at least as far as the 11th century, the total number of Jewish residents has always been quite small, so they never presented the target for bigotry found in Germany, Russia, or France. Gifford notes that "Jews are first mentioned as resident in Ireland in eleventh-century documents; Henry II acknowledged their presence (and legitimated it) by assigning custody of the King's Judaism in Ireland to one of his lords in 1174. From the time of the Norman Conquest the King's Judaism meant that the Jews were literally the king's chattel, but in practice they were protected, their rights to free exercise of their religion guaranteed and their businesses as merchants and moneylenders relatively secure. Jews were expelled from Ireland, as from England, in 1290 and were resettled in both countries under Cromwell in the mid-seventeenth century."
At the turn of the 20th century, the small number of Irish Jews was increasing. Gifford observes that the 1904 edition of Thom's directory records 3,898 of them in 1901, as compared to 1,779 in the 1891 census. By the late 1940s, the Jewish population in the Republic was approaching 6,000, but it has since declined to nearly the 1891 level. In the 2006 census, 1,930 Jews lived in the Republic. (All of these figures of course beg the question of what defines a Jew. By the traditional definition of Jewish maternity, Leopold Bloom himself does not qualify.)
Of the so-called Limerick pogrom, Frank McCourt writes, "Because I grew up in Limerick, the only city in Ireland with an anti-Semitic blot on its escutcheon, I've followed the Jewish thread in Ulysses. In January 1904 a Limerick priest, John Creagh, stirred the people up against the Jews who, he said, had shed Christian blood. Richard Ellmann says, 'Eighty members of the Jewish community were driven out, and only forty were left. Then Creagh was withdrawn from the community.' (That same Creagh, obviously a madman and not the first to be tolerated by the church, was then sent to Australia where he preached against the aborigines.) If Leopold Bloom is Jewish and anti-Semitism a theme in Ulysses, why did Joyce fail to mention the Limerick incident? He must have known about it. Ellmann tells us he did, and that makes it gospel" (Foreword to Yes I said yes I will Yes: A Celebration of James Joyce, Ulysses, and 100 Years of Bloomsday, ed. Nola Tully).
The anti-Semitic actions in Limerick began in the 1880s and 90s, but Father Creagh took them to a new level, charging the Jews with the two things that Mr. Deasy associates them with—practicing usury and rejecting Christ—as well as consorting with Freemasons. Many of the Jews who fled Limerick went to Cork, intending to embark for America from Queenstown harbor, but they were warmly welcomed by the people of Cork and settled there.