Where did the use of jack o lanters origionate?

Where did the use of jack o lanters origionate?
When the Irish Potato Famine (1845-50) devastated Ireland, over 700,000 fled to America, bringing the carved-turnip custom with them. Unfortunately, turnips were not as readily available in their new home. Pumpkins, however, could be found in abundance and were a whole lot bigger and easier to carve.Throughout Ireland and Britain, there is a long tradition of carving lanterns from vegetables, particularly the turnip, mangelwurzel, or swede. But not until 1837 does jack-o'-lantern appear as a term for a carved vegetable lantern, and the carved lantern does not become associated specifically with Halloween until 1866.