It's been several years since I posted here, and I still don't plan to post regularly. But I had an idea about the possible origins of the holiday of Purim, which I wanted to share. As far as I know, this idea is not found anywhere else, and obviously because of that, it's not backed with fancy sources. It's my own idea, and should therefore be subject to an extra critical eye, as there very well may be obvious things I'm overlooking. Anyway those caveats aside, let's begin.
The Question - How did Purim start?
In my original post on Purim, I noted that the holiday is very strange, and that there does not appear to be any Persian, Babylonian, Canaanite, or other cultural holiday around this time period for the Jews to have based Purim off of. Since the story itself is definitely ahistorical, it is interesting to wonder how the whole thing got started in the first place. There are two key features that bring me to the hypothesis I'll lay out in this post.
1) The holiday, and the book of Esther, are both focused on humor and satire.
2) The timing of the holiday is exactly one month before Pesach (Passover).
We'll see why these two facts lead me to the idea that Purim bears significant similarities to the modern day "holiday" of April Fools. But before we get there, we need to digress a bit and talk about the calendar.
How long is a year exactly?
The Jewish calendar is a lunar calendar, with months beginning with new moons. Lunar months are around 29.5 days long, which means that a lunar year of twelve months tends to be about eleven days shorter than a solar year. If you measure a year of twelve months then the two calendars will gradually desynchronize. This is exactly how the Islamic calendar is run, and the result is that major Islamic festivals can fall at pretty much anytime in the solar year. Ramadan can be in the summer or the winter. In Judaism such a solution would not work because of the specification that Pesach fall in the springtime. This requires the calendars to be synchronized in some manner.
The solution to synchronizing the two calendars was first practiced in Babylon and was called intercalation, or in common terms, making a leap year. The Babylonians would add an extra month at the end of their calendar year (like Jewish calendars, the Babylonian last month was Adar). Babylonian mathematicians figured out that you could synchronize the two calendars over a 19 year period by adding 11 extra months. This scheme would eventually be adopted in Judaism as well, but not until past the Talmudic period. What did they do before then?
The Talmud in Sanhedrin describes the laws of adding extra months. If you're interested it begins on 11a and continues for about four pages. It's far too long even to summarize. Even though there is significant debate over how you decide when to intercalate, all sources agree that one of the key deciding factors in the decision is the tekufah, or the equinox. The gemara brings a source that the timing of the equinox suffices alone to decide to add an extra month, and that other signs such as crop or tree blooming are of lesser importance. The equinoxes and solstices were key calendar markings in ancient cultures. In Judaism, the equinoxes marked the beginning and end of the rainy season, and thus had agricultural importance. The holidays of Pesach and Sukkot are essentially described by the equinoxes.
Another important feature of the leap year decision is that it needed to be made from a central location (namely Israel) and it needed to be made by a Nasi. This makes sense because you don't want different cultures declaring leap years differently and observing holidays on different days. The latest day that they could declare a leap year was the 13th day of Adar. Supposedly this would give enough time for Passover preparations.
So what in the world does this have to do with April Fools? The origin of April Fools is a bit obscure. One common hypothesis, and the one that is important for this post, is that the holiday came about because people used to celebrate New Year's between March 25 and April 1. When most regions adopted Jan 1 as New Year's Day, they made fun of the people who celebrated it on April 1, by having a lighthearted April Fool's holiday. Whether this is the actual origin or not is not really important. What is important, is the idea of a holiday that begins because different groups are celebrating a joint holiday on different days.
So what does this have to do with Purim? Let's imagine a scenario. You're a Jew living in Persia, and it's the twelfth day of the thirteenth month since the beginning of last year. You're probably preparing for Pesach. The fourteenth day rolls around and you start your seder, when all the sudden a messenger from Israel comes and says to stop because a leap year has been declared and it's not actually Pesach for another month. What do you do now? You already had this feast prepared. You might as well finish it.
Let's go a bit further. The thirteenth month starts and you're not sure whether it's Adar II or Pesach because you haven't heard about the leap year declaration yet. So you decide, just to be safe, you'll prepare a festive meal for the 14th of this month too. Then if a leap year is declared, you'll just prepare another one for the next month.
These kinds of scenarios might play out fairly often in places far from Israel, where it took a long time to get the message about leap year declaration. Namely Persia, where many Jews lived, and where Purim appears to have originated. The idea is that just like April Fools is New Year's Day on the wrong day, Purim is Pesach on the wrong day. Just like everything else, as the holiday grew in popularity, it eventually became part of Jewish culture as a whole.
This also helps explain why Purim is always celebrated in the leap month if there is one. In the April Fool's theory of Purim, the holiday would have originally been celebrated only on these months. It also help explain why the holiday is light-hearted and satirical, just like April Fool's is.
So there you have it. Purim is the original April Fool's.