The famine of the 1840s brought to a crisis Irish discontent with English rule, culminating in the abortive Young Ireland uprising of 1848, led by William Smith O'Brien. Vast numbers of embittered Irishmen emigrated to the United States, Australia, South America, and Canada, where they redoubled their agitation against England. John O'Mahony, one of those revolutionists driven abroad in 1848, was the organizer of the movement in the United States, and it was he who gave the society its name.
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