The Commercialization Timeline

1. 1840s: Mass-produced Valentine cards in America

2. 1868: Cadbury creates first heart-shaped chocolate box

3. 1913: Hallmark begins producing Valentine's cards

4. 1980s: Diamond industry launches Valentine's campaigns

5. 2000s: Digital age transforms Valentine's marketing

By the 1900s, Valentine's Day had transformed from a religious observance into a commercial celebration of romantic love.