In the eighth century, Pope Gregory III designated November 1 as All Saints’ Day, a day to honor Christian saints and martyrs. All Saints’ Day later became known as All Hallows’ Day, and the night before, October 31, became known as All Hallows’ Eve, and eventually Halloween. 

The Irish and Scottish brought their folklore about a trickster named Jack to America, where they found pumpkins, which were easier to carve than turnips. The story of Jack-o’-lantern is said to have inspired the Irish to carve faces into pumpkins to ward off evil spirits.