Is this a trick question? Perhaps.
On the one hand, you may think that a Christmas cookie is one that you make (and eat) around Christmastime. But is that all there is to it? Because certainly Christmas cookies aren't just a result of everyday recipes dressed up with red and green sprinkles or dye, are they? It seems to us that certain cookies, while available at other times of year, proliferate around the holiday season--spritz cookies, gingerbread, cutout sugar cookies, for instance. In addition, how is it that nearly every family has a unique collection of cookies--ranging from bonbons to melt-in-your-mouth meringues to Rum balls--that only come out around the holidays?
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).