<p>Every year, Americans buy some <a href="http://www.greetingcard.org/AbouttheIndustry/tabid/58/Default.aspx">145 million</a> cards for Valentine's Day. But the holiday wasn't invented by greeting card companies. It started with the pagans.</p><p dir="ltr">The holiday's origins trace back to the Roman Empire and the festival of Lupercalia. On February 15, Romans celebrated the advent of spring with fertility rites and a matchmaking lottery between men and women.</p><p dir="ltr">In the late fifth century, the Catholic Church outlawed Lupercalia and established St. Valentine's Day. The church named the new holiday after Saint Valentine, who may or may have not been a Roman martyr who refused to give up his Christian faith. (There were several Saint Valentines in church history, apparently.)</p><p dir="ltr">According to one legend, the holiday's namesake sent his jailor's daughter a note after falling in love with her, signing it "from your Valentine."</p><p dir="ltr">Valentine's Day probably became associated with romance during the Renaissance, which is when people began exchanging valentines. In the 1840s, stationery store owner <a href="https://www.mtholyoke.edu/175/gallery/esther-howland">Esther Howland</a> cashed in on the trend by selling America's first commercially produced valentines.</p><p dir="ltr">To celebrate Valentine's Day, illustrations editor Kathy Moran pulled some of her favorite pictures of couples kissing from our archives. Above, a young girl and boy dressed in traditional Swiss clothing share a kiss in a 1915 <em>National Geographic</em> photo.</p><p dir="ltr">(Read more about <a href="http://news.nationalgeographic.com/news/2012/02/120213-valentines-day-gifts-cards-history-facts-naked-romans/">why we celebrate Valentine's Day</a>.)</p><p dir="ltr"><em>—By Becky Little, photo gallery by Kathy Moran</em></p>

A Kiss Is Still a Kiss

Every year, Americans buy some 145 million cards for Valentine's Day. But the holiday wasn't invented by greeting card companies. It started with the pagans.

The holiday's origins trace back to the Roman Empire and the festival of Lupercalia. On February 15, Romans celebrated the advent of spring with fertility rites and a matchmaking lottery between men and women.

In the late fifth century, the Catholic Church outlawed Lupercalia and established St. Valentine's Day. The church named the new holiday after Saint Valentine, who may or may have not been a Roman martyr who refused to give up his Christian faith. (There were several Saint Valentines in church history, apparently.)

According to one legend, the holiday's namesake sent his jailor's daughter a note after falling in love with her, signing it "from your Valentine."

Valentine's Day probably became associated with romance during the Renaissance, which is when people began exchanging valentines. In the 1840s, stationery store owner Esther Howland cashed in on the trend by selling America's first commercially produced valentines.

To celebrate Valentine's Day, illustrations editor Kathy Moran pulled some of her favorite pictures of couples kissing from our archives. Above, a young girl and boy dressed in traditional Swiss clothing share a kiss in a 1915 National Geographic photo.

(Read more about why we celebrate Valentine's Day.)

—By Becky Little, photo gallery by Kathy Moran

Photograph courtesy National Geographic

For Valentine's Day, Photos of Some Sweet Smooches

From young love in Switzerland to a sweet embrace in Paris, see our collection of kissing photos.

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