Throughout the 1800s and early 1900s the amount of Irish people immigrating to America increased greatly. The peak of the immigration occurred between 1845 and 1855 due to the spread of famine in Ireland which took the life of near a million people. The Famine was caused from a virus that infected the potato crops causing them to rot and decay. The disease was also known as the "Potato blight." Because of the great famine a vast amount of the Irish people were forced to migrate else were. The poor Irish farmers were sincerely affected by the blight since they were living of their crops. The potato was a crucial crop for the farm lands and a valuable food source. It was estimated by the BBC that the potato provided approximately 60 percent of the nation's food needs during the 1800s. .
Before the mass emigration, Ireland was home to a majority of farmers who often lived through severe poverty. The lands of the Irish farmers where commonly owned by Scottish and English protestant landlords and subjected Irish Catholics of oppression. Even in their own country the Irish people and especially the farmers did not have an ideal lifestyle. One example of the oppression the Irish suffered would be that no Irish catholic was allowed to buy a piece of land and were given limited basic rights. The farmers were also issued a very minimal wage which is why the poverty was massive at the time.
When the potato blight then struck, massive amounts of Irish people migrated to prevent starvation and because of the deprived lifestyle that they had. People where migrating before the potato blight too however the disease which occurred in 1845 worked as a breaking point causing millions to migrate to America as you can see on the graph on the right. The Central Statistics Office of Ireland show an Irish population of 8.2 million in 1841 and just a decade later it shows a population of 6.