As you are undoubtedly aware, some salespeople will use just about any holiday as an excuse to sell you something. There are a few holidays, like Christmas and Hanukah, which are especially good for sales, because they’re good for giving gifts. Other holidays, like Thanksgiving, can be a harder sell unless you have a clear tie-in—like recipes. Even then you’ll find car dealers using the holiday event (which generally means people have the day off of work, which they could use to spend hours browsing vehicles and filling out paper work) to boost their sales.
You shouldn’t try to sell your books during every holiday that comes along. There is, after all, a reason people make fun of car dealers. However, you should look for ways to tie your book in with particular holidays that are meaningful to you and/or your characters. If you can, you may even want to align your book releases with certain holidays that can add special attention to your subject matter.
A love story can coincide with Valentine’s Day. A story of renewal and redemption can coincide with Easter. An exodus story can coincide with Passover. A parental story can coincide with Mother’s Day or Father’s Day. A war story can coincide with Memorial Day, Veterans’ Day, or Independence Day. Arbor Day is a good day for a book that celebrates nature and New Year’s Day is a good day for a book that celebrates renewal.
Think of what your book means to you and whether there’s a holiday you can target, either to give your annual marketing efforts a boost or to launch your book.