Postcards without pictures were used in various European countries from the 1860's onward. The addition of pictures soon followed, but in Britain the postal laws did not allow companies to produce mailing cards until 1898. Other countries, including United States, allowed it a little earlier. This immediately let to an avalanche of new postcards. To collect them was quickly a craze. From 1890 until about 1920 there was a torrent of fresh images and they were bought and sent by the billions. Of course picture postcards continued to be made and used after 1920, but the First World War interrupted their production and the public lost interest. This period, from the 1890s to 1920 can be viewed as the golden age of the picture postcard.
The different designs that appeared on picture postcards are uncountable. There are few subjects that were not pictured. The card publishers tried everything they could think of, including animals, history, humor, imaginary beings, sports, exploration, architecture, inventions, main streets, flags, politics, religion, automobiles, beautiful women, cute children, world's fairs, seashells, advertising, puzzles, celebrities, fashion–the list is endless.
Holidays were the overwhelmingly favorite theme, and each holiday inspired many cards