The 12 days of Christmas began in the 16th century, when Christians in England celebrated the birth of Jesus Christ. The custom of giving gifts on each of the 12 days leading up to Christmas was introduced as a way to commemorate the Twelve Apostles and the gifts they brought to Jesus on the day of his birth. Today, the 12 days of Christmas are celebrated around the world as a way to spread joy and generosity during the holiday season.