When people migrate to another place these are the main reasons.
- Can't provide for their basic needs
The Great Hunger in Ireland triggered by the failure of the potato crop in 1845 led to the single greatest loss of life in Europe. While over a million Irish starved to death and another million were forced to emigrate, food was being forcibly exported from the Island by its foreign rulers - food sufficient to feed the people several times over. This period represented the blackest days of Irish history.
Photo and Caption courtesy of