’Tis the season to spend lots of money on extravagant, largely useless gifts.

At least that’s what the latest figures from the National Retail Federation would suggest. This November and December, U.S. shoppers will likely spend upward of a trillion dollars, with the bulk of the money going toward Christmas gifts.

It wasn’t always so. Before the 19th century, Christmas remained a relatively minor holiday rooted in pagan rituals. But as the U.S. industrialized and became the world’s largest economy, Christmas became a celebration of commerce and consumption, with Santa Claus its greatest salesman.