Wreaths actually began in ancient Persia, and they were not hung from the wall, but placed on the head. The first wreaths were originally head dresses worn at festive celebrations. No one is quite sure when they made the switch to wall decorations as we know them today, but the theory is that the wreaths were placed on wall-mounted hat racks and eventually became a decoration on their own.
Wreaths as we know them today were first popularized in the Germanic region of Europe. They began the popular tradition we have today of hanging decorative wreaths at Christmas time to celebrate the season. They typically used Advent Wreaths, which contain rings of candles in coniferous tree branches.
Today, wreaths are commonly seen throughout the entire year, not just at Christmas. Still, though, we have seasonal wreaths especially for the holiday season. Products like the WreathKeeper from treekeeperbag.com are great for storing them when the holidays are over.