Irish Hunger Memorial New York, Battery Park, NY

Ireland's population prior to the famine was 8.5m. After it was about 5m. In excess of 1m died of hunger and disease in Ireland, and over 2m emigrated. It is estimated that about 50% of these died in transit from disease, hunger and overcrowded conditions on board ships, referred to as Coffin Ships.
The British authorities thought that the country was over crowded, and saw the famine as an opportunity to reduce numbers. They saw it (the famine) as providence (and due to the sin of "popery") and any relief they were willing to give was to be paid for by the Irish.
In the meantime the country continued to export food, watched by the starving Irish, to support the rich lifestyles of landlords, many of whom did not live in the country.