Special days – or holidays- in novels are actually surprisingly rare. Very few books take advantage of the summer or winter solstice and other days even though they give you many writing opportunities.
- Putting in a holiday gives readers an opportunity to see how your character interacts with other people.
- Since a lot of attention of holidays are on those running it, people of power are normally right in the spotlight so it can show where your character sits in a position of power.
- Food. There is always food at celebrations, so it gives you a chance to engage the sense of taste and smell for readers, and it also shows what it is the people of your world eats.
- You could use it to show things to come. For example, perhaps a ghost does not disappear after Halloween. Is that hinting of things to come? Is the veil between the ghost world and our own getting thinner?
- It gives opportunity to show thoughts on power. For example: the Kings or Queens birthdays, and also what day they became the king or the queen. Perhaps the people just use it as a day off to drink, perhaps they reluctantly celebrate because they have to, or maybe they go all out because they actually love the king or queen. This is a quick opportunity to show the average persons perspective on whoever is in charge.
Need some examples of what holidays you could have?
Perhaps to mark spring, the whole village goes out and plants seeds on the same day. This marks rebirth and the start of a new year, so to amplify this, if a person wants a fresh start, they can burn everything they own and even cut and burn their hair, and from that day on the villagers must accept this person is a new person. They can not hold grudges on them because they are no longer the person they were the day before.
Another example is harvest festivals. Most places in the world celebrate the last day of harvest had have a great feast. Some even give some of the harvest to some sort of spirit or fair folk.
There are many ways to use holidays to your advantage in writing, and they are an often skipped over tool.