Immigration from Ireland hit its peak in the 1850s, when more than a million Irish immigrants -- many fleeing their homeland because of famine -- became legal permanent residents.
It's fallen quite a bit since then. In the 2000s, the number of Irish legalizing was only about 1.5 percent of what it was back in its heyday.
Yet Irish interests quietly remain part of the immigration debate in Washington.
An immigration bill being considered in the Senate would give special consideration to several countries for future immigration. South Korea, Poland and Canada are all hoping for their own part of the deal. And so is Ireland.
This wouldn't be the first time the Irish have gotten special consideration.
One of the most notable examples was the so-called diversity lottery. During the early '90s, as the program was getting off the ground, 40 percent of visas were earmarked for Irish, thanks to the late Sen. Ted Kennedy (D-Mass.)
But that visa allotment was temporary, and groups like the Irish Lobby for Immigration Reform (ILIR) are hopeful the Senate bill will create a more permanent program. A provision added by Sen. Charles Schumer (D-N.Y.) would make 10,500 renewable visas available to Irish nationals each year.
To see why the Irish might need their own deal, I spoke to Niall O'Dowd, the founder of the ILIR and the editor of the New York-based Irish Voice.
Adverse effects of the 1965 immigration law
Prior to 1965, the immigration system overtly favored European nationals over people coming from other parts of the world. Then Congress passed an immigration bill that scrapped that system in favor of more even visa distribution.
While that meant opportunities for immigrants from Latin America and Asia -- and ended clear discrimination -- it cut visas for European nationals.
"It's been impossible for Irish people to emigrate legally to America since 1965," O'Dowd said. "The new preferences militated against Irish people; indeed, any people coming from Europe."
He's right. While the migration flows from Ireland are much smaller than from a place like Mexico, for example, you can see a drop in Irish that were able to become legal permanent residents around the time that the 1965 law was passed.
That said, part of the reason the number of visas to Irish dropped was that they were no longer benefiting from a discriminatory system.
Irish Still Come, Just Illegally
Niall O'Dowd estimates that there are 50,000 undocumented Irish living in places like New York, Boston and Chicago.
Out of 11 million undocumented immigrants, that isn't a huge number. But O'Dowd believes that the poor economy in Ireland and the historic migratory ties to the U.S. will keep Irish people coming.
"Our people are still coming here, but they're coming illegally, which is no way to go," he said. "We're trying to regularize future flow."
Creating legal pathways for immigrants who would be coming anyway makes sense. But the countries that send the most people illegally aren't getting this type of deal.
Which makes you wonder, why Ireland...
A Shared History -- and Connections
"We've always had a program to help Irish immigration," Sen. Schumer said at an immigration reform hearing on Thursday. "America and Ireland are bound together by history, traditions and common ancestry."
While that's true, a lot of nations share history and heritage with the U.S.: Germany, Italy, Mexico, the Philippines. But we don't typically use that as a basis to give out visas.