From the New York Times:
At year’s end, people around the world indulge in food rituals to ensure good luck in the days ahead. In Spain, grapes eaten as the clock turns midnight — one for each chime — foretell whether the year will be sweet or sour. In Austria, the New Year’s table is decorated with marzipan pigs to celebrate wealth, progress and prosperity. Germans savor carp and place a few fish scales in their wallets for luck. And for African-Americans and in the Southern United States, it’s all about black-eyed peas.
Not surprisingly, this American tradition originated elsewhere, in this case in the forests and savannahs of West Africa. After being domesticated there 5,000 years ago, black-eyed peas made their way into the diets of people in virtually all parts of that continent.