Irish people immigrated to the United States in large numbers because a disease known as blight destroyed their potato crops. This crop failure began in 1845 and caused a food shortage. What was the significance of the Irish Americans?
More than 7 million Irish immigrants have come to America since the 1600s. This mass movement transformed Irish society and played a significant role in shaping American politics, religion, culture, and economics during the country’s most formative years. More than 40 million people in the United States claim some degree of Irish ancestry.
Colonial and Pre-Famine Immigration
Approximately 50,000 to 100,000 Irishmen, over 75 percent of them Catholic, came to America in the 1600s, while 100,000 more Irish Catholics arrived in the 1700s. A small number of prosperous merchants formed communities in Philadelphia and other cities, but most immigrants were indentured servants who eventually blended into the mainstream society. A few were prominent citizens, like wealthy Charles Carroll who migrated to Maryland in 1681, establishing a family that produced the only Catholic signer of the Declaration of Independence and the first American archbishop.
Between 250,000 and 500,000 Protestant Irish arrived in the eighteenth and early nineteenth centuries. While some were southern Irish Anglicans and Quakers, over three-fourths were Scotch-Irish Presbyterians from Ulster. In search of land and religious freedom, these "Wild Irish" settled in New England, New York, and Pennsylvania, later migrating to the wilderness backcountries of Virginia, Georgia, and the Carolinas. Known for their hatred of the British and their rugged individualism, many fought bravely in the American Revolution. More came in the early 1800s to settle Kentucky and Tennessee, becoming the nation’s first "Indian fighters" and producing such American heroes as President Andrew Jackson (1767–1845) and frontiersman Davy Crockett (1786–1836).
The end of the Napoleonic Wars in 1815 caused widespread changes in Irish society and opened the flood-gates of poor Catholic immigration. Landlords began to turn from grain production to cattle, raising rents and evicting tenants by the thousands. During this time, the population in Ireland rose from 6.8 million in 1821 to 8 million in 1841, with the largest increase among poor cottiers—landless laborers who received access to land for working the landlord’s crops. Partible inheritance (dividing land among all sons), early marriage, and high fertility doubled their numbers from 665,000 to 1.3 million between 1831 and 1841. Fathers could no longer provide for every child, creating scores of young men and women with no alternatives but delayed marriage, permanent celibacy, or emigration. As a result, 1.3 million people left Ireland for America between 1815 and 1845.
Famine Immigration and Settlement
Conditions for those who remained behind in Ireland continued to worsen. As plots of land shrunk and the population grew, cottiers came to rely increasingly on the potato, a nutritious root that grew quickly and easily in Irish soil, as their main source of food. In August 1845, a fungus destroyed the potato crop, returning for the next four years and causing widespread destruction. Despite assistance from public and private sources, approximately 1.5 million people starved or died of famine-related diseases between 1846 and 1855, the most during "Black ‘47." Another 2.1 million emigrated, mainly to the United States, accounting for almost half of all immigration to the States during the 1840s and over a third during the 1850s.
In America, initial sympathy for the starving peasants gave way to anti-Catholic hostility as they began to arrive in droves, forming enclaves in Northern cities. In Boston, for example, immigration rates rose from 4,000 in 1820 to 117,000 in 1850. By the 1850s–1860s, 28 percent of all people living in New York, 26 percent in Boston, and 16 percent in Philadelphia had been born in Ireland. Irish Catholics also dominated immigration to Southern cities before the Civil War (1861–1865); New Orleans was the second-largest port of arrival after New York by 1850.
Various charitable and social organizations helped the Irish settle into American life, while such financial societies as New York’s Irish Emigrant Savings Bank (established 1851) assisted immigrants with sending remittances back home. The most important institution was the Catholic Church, which created a national network of churches, hospitals, schools, and orphanages. Irish priests, such as New York’s Archbishop John Hughes (1797–1864) and Charleston’s Bishop John England (1786–1842) dominated the hierarchy and shaped the course of American Catholicism. On the local level, the parish church served as the center of Irish American life, becoming the means of both preserving ethnic culture and Americanizing immigrants.
Their service during the Civil War also helped the Irish gain respect and acceptance. While criticized for their role in the 1863 New York draft riots, as many as 170,000 Irish-born men served in the Northern army. In the South, the Irish contributed the largest number of troops of any foreign-born group.