The Christmas Pickle is an interesting modern Christmas custom, one that no one is quite sure why it exists at all.
In the 1880s Woolworth stores started selling glass ornaments imported from Germany and some were in the shape of various fruit and vegetables, and quite likely, pickles.
Around the same time, it was claimed that the Christmas Pickle was a very old German tradition and that the pickle was the last ornament hung on the Christmas tree. The first child to find the pickle got an extra present.
Possibly a myth, but what the heck…