We know that a huge number of Americans claim Irish ancestry. But this interactive map from Pew research shows just how this happened. It shows the patterns of immigration to the US since 1850.

The map is part of a study of immigration patterns over the last 150 years. It's eye-opening to see just where the people came from and where they settled. For 30 years the Irish were the main immigrant group in the USA. The Germans were the second.

This is an astonishing concept when you consider just how small Ireland is.

Let's take a look at how this played out;

In 1850 the population of the US was 23 million. In that year 1 million (4% of the population) were immigrants from Ireland. Germans were the 2nd most populous immigrant group with 600,000 travelling.
The vast numbers of Irish had probably settled within the last 3 years since the Famine had really started to hit hard.

By 1860 the numbers leaving Ireland had increased even further. There were now an extra 600,000 Irish-born people in the country. The Germans increased their number as well to 1.3 million.
By this stage the Irish began to leave the traditional Eastern coast and were venturing further west.

By 1870 the numbers leaving Ireland were slowing as the famine abated; the number of Irish-born increased by only 200,000 over the previous decade. Of course the number travelling was probably greater as we do not have figures for those earlier emigrants who died over that period. Nor do we have accurate figures for the number who died en-route.

By this time the route to the West was established and Irish were the dominant immigrant group in the area.

In 1880 for the first time the number of German-born people in the US outnumbered the number of Irish-born. The Irish were also no longer the dominant emigrant groups in any but a handful of Easter states.

Surprisingly though the numbers who came to the US would slow further it took until 1920 for the Irish to drop out of the top 5 of foreign-born people in the US. It can be assumed that this meant at least a further 1 million people emigrated during those 40 years.

Impact On Ireland

In the 30 years from 1850 to 1880 the number of Irish who moved from their small island to the USA was in excess of 2 million. A further 1 million emigrated in the next 40 years.

In addition to these numbers even greater numbers emigrated to the UK, Europe, South America and Australia. A destiny as emigrant was well established by the Famine and it continued to decimate the Irish population for over a century. The population dropped form 8 million in 1840 to 3 million in 1980. In that year approximately 200,000 people left the country.

Only in the 21st century did the population start to grow again, first with returning emigrants and then with actual immigrants from other countries. Approximately 10% of the current Irish population was not born in the country.

The economic collapse of 2008 has once again introduced emigration to Ireland, and we have become the OECD country with the highest rate of emigration. Despite this the population continues to grow and a quarter of all births are to foreign-born mothers.

Whether this ability to absorb such large numbers without strife, and to do so even during hard financial times, is something that comes from the experience of emigration is of course impossible to say for certain. But it must surely be a factor?

Impact On The USA

The influx of such large numbers of people from Ireland at the beginning of its own growth obviously had a strong influence on America. Some of this is positive but much was also negative, at least for a while. The incoming numbers of Irish were among the most impoverished people on the planet and they spoke a different language and had a different religion from the existing population.

The US population at the time was primarily derived from British stock and this probably also influenced the attitude to the newcomers.

Nevertheless once the Irish became established they had a direct impact on the growth of the USA. They built the cities of the East and, as we saw from the map of 1870 they moved out west at an early stage.

As the only Catholic group they were seen suspiciously by their fellow countrymen and immigrant alike. As recently as John F. Kennedy's run for present there was suspicions about his loyalty to his country.

Of course cities such as Boston are very Irish but across the US the Irish have had a strong influence on culture and traditions. Is there a state that doesn't have a Dublin?