It’s hard to imagine Valentine’s Day without the traditional greeting cards, whether accompanying a gift of flowers and candy, or sent between children in a school room. For commercial greeting card companies, February 14th is as important to them as the December holidays, Easter, and Mother’s Day.

Valentine’s Day as a celebration of romantic love predates printed greeting cards by a few centuries. In fact, the reason that sending romantic greeting cards became popular was because of the most un-romantic thing you can imagine: a reduction in postage rates.

In 1765, Parliament authorized the creation of “Penny Posts” that used a uniform rate of one old penny per letter throughout Great Britain and Ireland. Printers took advantage of the ease with which people could send letters to each other on Valentine’s Day by crafting cards with love poems on them. Many of these verses were collected in 1797 in the book The Young Man’s Valentine Writer, which was a resource for the lover with a romantic soul but not the most confident poetry style.

By the mid-19th-century, the Valentine’s Day greeting card was flourishing across England. Although people still followed a tradition of creating handmade Valentine’s Day cards from lace, ribbons, and flowers, commercially produced cards now overtook them. In 1835, the English post office mailed 60,000 valentines. As production expenses dropped, the English card manufacturers branched out creatively with humorous and sometimes vulgar cards… many of which we would find startlingly familiar in the 21st century. One of the common jokes on these cards was to design them to look like marriage certificates or court summons.

Across the Atlantic, the United States was slower to embrace the popular British custom. It wasn’t until 1847 that a U.S. printer mass-produced greeting cards for Valentine’s Day. Only two years later, American journalists noted how rapidly people in the country had embraced the tradition, turning into a fad that has never died down. The woman who printed the first U.S. Valentine’s Day card, Esther Howland, is today recognized by the Greeting Card Association with the annual “Esther Howland Award for a Greeting Card Visionary.”

The greeting card industry certainly has reason to thank Ms. Howland. Her idea of going into business printing romantic greeting cards, which came to her after she received a traditional English valentine when she was 19 years old, now sells 190 million cards in the U.S. every year. That number doesn’t include the smaller exchange cards used in elementary school classrooms, which would swell the number to 1 billion. (Who receives the most Valentine’s Day cards each year? Teachers!)

Whether you send out Valentine’s Day cards—handmade, store-bought, digital—or not, we at Mister Sparky hope you have a happy February 14th.