To discover the true meaning of Christmas (cookies), we had to look back--way back--in time. Now, it's no secret that sweets have been part of holiday rituals since long before Christmas was a declared a holiday (which was in 1870, in case you were wondering). But according to Foodtimeline.org, it was a combination of Eastern spices and European flair that contributed to the cookie's success:

Ancient cooks prepared sweet baked goods to mark significant occasions. Many of these recipes and ingredients (cinnamon, ginger, black pepper, almonds, dried fruits etc.) were introduced to Europe in the Middle Ages. They were highly prized and quickly incorporated into European baked goods. Christmas cookies, as we know them today, trace their roots to these Medieval European recipes. Dutch and German settlers introduced cookie cutters, decorative molds, and festive holiday decorations to America. German lebkuchen (gingerbread) was probably the first cake/cookie traditionally associated with Christmas.

Naturally, cookies lend themselves very nicely to cookie cutters, which we would surmise is one reason why they tended to stick around as a Christmas tradition--not to mention that they have a long shelf life, travel well, and are made in larger batches that imply bounty (that is to say, even though 24 cookies and one cake may have the same surface mass, the number of items can fool us into feeling as if there is more to share).

Of course, the article goes on to state that sugar cookie type recipes descended from English traditions; perhaps their trip over the Atlantic was the inspiration for Animal Crackers, which were originally designed as Christmas ornaments. 

While the tradition of Christmas cookies may have its roots in Medieval Europe, and while we may associate some cookies with the holidays more than others, it's also true that Christmas cookie recipes today come from all over the world--it would not be unusual to see German Lebkuchen, Scottish Shortbread, Italian Pizzelles and all-American Cornflake wreaths sharing the same plate. Why so? Well, we surmise that it's an illustration of evolution--as people immigrated and adapted, naturally they would want to honor their culture's recipes with the Christmas cookie tradition. While this may blur the boundaries of what is a Christmas cookie and what is just a cookie, it certainly does make the variety and joy of discovery at holiday parties a whole lot more fun.