One of the books I am reading now: Leon Uris' Trinity (1976). It's a novelized visit to a sorrowful piece Irish history, and so well-done that it's difficult to imagine that Uris was not Irish.
That potato fungus, and its consequences, killed or drove away over 1 million Irish. The book puts you there. Mrs. BD is half-Irish, and tells me "Stop" when I read sections to her. Mostly the Catholic peasants had the worst time. They were sharecroppers, peasants. The Scots Presbyterians and the Brit Anglican overlords did somewhat better, at the expense of the sharecroppers. It is heartbreaking.
Lucky thousands made it to Canada and the US. Luckily for the US and Canada. The Brits were no heroes of the history, but they were stuck with the tragedy too. It was complicated, like all such things.