I'd like to know about the Irish great famine in the 1840s. Also, I want to know about the causes and symptoms of potato blight.
The great famine of Ireland took place in 1845-1849, and it is said that about a million people died of hunger during those years. In the early 1840's around a third of Irish people depended on the potato as their main source of food, and thus the destruction of the potato harvest because of potato blight in 1845 launched a catastrophe.
More information about the famine:
Potato blight is a potato disease caused by a fungus. Its origins are in America, from where it spread to Europe by a shipment of seed potatoes destined for Belgian farmers in 1845. Potato blight first affects the leaves and later the actual potatos causing the to change colour and, eventually, turn into a soggy, foul smelling mass.
More information about potato blight: