From The Writer’s Almanac:
Today is Boxing Day and St. Stephen’s Day in England, Canada, and several other countries. The origins of this national holiday are not certain, but the holiday might have started from an old custom of wealthy estate-owners giving small gifts or money, wrapped in boxes, to their servants and those who worked for them. Servants were needed on Christmas to help with their masters’ holiday events, so they often were given a rest the next day. St. Stephen is honored today for being the first Christian martyr, having been stoned to death for blasphemy.