One of the greatest factors that led to massive emigration from Ireland to the United States in the mid 1800 was

In the mid-1840s Famine due to potato blight was the main cause of massive Irish immigration to the United States which destroyed the staple food of the Irish diet. Thousands of the peasants were driven from their cottages due to hunger, poverty and were forced to Immigrate to North America. These peasants had no skill and experience of adaptation to the new country. However, many immigrants also died while crossing the ocean due to diseases and ships were known as coffin ships.