How to Tell Time in a D&D World Part 1: Calendars

Recently, I had a discussion with one of my players about his homebrew world. He recounted to me how he created his world's calendar, from the days of the week and number of months to how they were named and why certain folk tracked them differently or not at all. His excitement about this lore was palpable. As I listened, I began to drift into my own world and think about how and why the calendar was made the way it was. At that time, I had an extremely basic calendar: twelve months, four weeks each, seven days in a week, all with uninspired names and origins.

Armed with inspiration from this creative player, I set out to research how the modern calendar was made, why various aspects of it worked the way they did, and reinvent my world’s calendar, seasons, holidays, and more.

This Worldforge article encompasses one of those three aspects: we are going to build a calendar, step by step, and learn about Earth’s time-keeping history concurrently. In good time, we will visit seasons, holidays & annual events, which should be a huge part of custom D&D setting. They all add lots of flavor. First, though, we need a calendar.

Let’s delve into telling time in our D&D worlds with part 1: calendars.

The Modern Calendar

While the tracking of time in its most basic sense, counting days and the like, has existed since prehistoric times (the Neolithic, in particular), calendars are also quite old, dating back to the Bronze Age. During eras before the Bronze Age, various peoples used megalithic structures to keep track of time. They would arrange stones in a particular formation and witness the progression of the sun throughout the year. This type of calendar was called a solar calendar.

As soon as ancient civilizations in the Near East developed their own styles of writing, they started tracking time in an organized, easy-to-digest way using written calendars. The oldest written calendar known to exist was the Sumerian calendar, closely followed by the calendars of Egyptians, Assyrians, and Elamites. Many of these calendars contained ten to twelve month-long years. These calendars, generally, were based on the position or phase of the moon and the time of the solar year. Each month witnessed the full waxing and waning of the moon, then restarted. They were called lunisolar calendars.

In 45 BC, Julius Caesar did away with the Roman calendar that was based on the calendars of ancient civilizations and created his own with the help of Greek astronomers and mathematicians. The Julian calendar no longer relied on the observation of the new moon. Instead, it used an algorithm that included a leap day every four years and outlined twelve months. Thus, the Julian calendar months became dissociated from the cycle of the moon. Over 1,000 years later in 1582, the Julius calendar was refined into the Gregorian calendar. That is the calendar most of the world uses today; it’s the modern calendar.

In tandem with the Gregorian calendar, this is how we tell time on Earth:

• 12 months in 1 year
• 4 weeks in 1 month
• 7 days in 1 week
• 24 hours in 1 day
• 60 minutes in 1 hour
• 60 seconds in 1 minute

What to Keep, What to Toss

That’s a lot to take in. With all of it in mind, how does it affect calendars and telling time in our fantasy worlds? What can we learn? What can we twist? What can we innovate? What can we make fantastical? But most important of all: is changing our calendars worthwhile? That’s a sure yes from me, of course. But not everything needs to be changed, else it will feel too alien. We should use Earth as a standard, then shift from it in interesting ways.

For example, we should stick to the following when building our own world’s calendar and system of telling time:

• 60 seconds in 1 minute
• 60 minutes in 1 hour
• 24 hours in 1 day
• 7 days in 1 week

That knowledge is ingrained in our minds and should be the standard in most of our fantasy worlds as well. If we change it up too much, our worlds will be too jarring to be believable. Our players shouldn’t need to learn that there are actually 30 seconds in a minute and 47 minutes in an hour—that’s rubbish. All of these standards of telling time should not be fiddled with.

What can be changed, though, are the following items:

• 12 months in 1 year
• 4 weeks in 1 month
• The name of the months
• The name of the days of the week
• How years are named
• How time periods are named

All of these can be shaped to our worlds and won’t be nearly as jarring as changing how many hours are in a day. We should leave those type of radical changes for peculiar places in our worlds such as the Elemental Plane of Fire or the Abyss—that’s where we can get wacky. For the Material Plane where the majority of adventures begin, let's keep information related to seconds, minutes, hours, et cetera identical to how they are represented in real life.

Time To Create

Armed with what we can change, now we need to think about whether we want to make changes. We should go through each of the items of the list above and ask ourselves: does this need to be changed? Would changing it make our worlds more compelling? Unique? Interesting? Could we wield this in our games? Is it just something we want to do? Let's arrive at a yes or no answer for each of the questions and then begin building.

Here are a few questions to ask ourselves while creating our time systems and calendars.

• Why are months separated the way they are? Is it based on the cycle of the moon or moons? The planes around the world? The seasons?
• What are the months named after? Heroes of the past? Common monsters? Legendary locales? Words in a forgotten tongue?
• How are the days of the week named? Using a combination of two languages? A simple word for each? Arbitrarily?
• Do years have names associated with them? Are they standalone numbers? Do the common folk keep track of the years that pass by?
• How are time periods named? Have there been multiple ages? Do a certain numbers of years constitute a time period?

As we continue to create, more questions should arise. We don’t always need an answer immediately—not everything about our calendars or time systems needs to be known. This leads to the next part.

Who created our worlds' calendars? That’s an important question we should know the answer to, but doesn’t need to be apparent to our players or most the individuals in our worlds. It’s likely many folk don’t know where the Gregorian calendar originates, people in our worlds might be similar. However, if we have this lore built out, we can make the calendar more believable. The answers to certain questions above might make more sense once we build out a creature, a faction, or even a civilization that created our calendars in canon.

The calendar could be the latest iteration of a thousand calendars, perfected over centuries of study. Or it’s brand new, recently released by a mysterious entity. Or perhaps the calendar is the only one the world has ever known and it was made by a civilization lost to time.

Here are four entities who could have created our calendars!

1. A cabal of dwarves obsessed with chronomancy who needed a way to orate their findings to simple monarchs.
2. A god of time and space who thought mortals would want a way to track their existence in the world.
3. An enlightened nation of philosophers and scientists who knew this would be the greatest tool in history and made everyone aware of that fact.
4. A humble minotaur who studied the stars and moons and deciphered how and why one day follows the next.

My World’s Calendar

This is an excerpt from my campaign setting guide, Handil’s Atlas of Eldar. It is my world's calendar.

In the common calendar of Aelonis, called the Thimaeven Calendar, days are 24 hours long, divided into day and night. Seven days make up a week, four weeks make up 12 of the months (the first and eighth months are 2 weeks each), and 14 months make up a year. The months correspond to the 14 prime planes of existence (see the Eldar Months table) and the prominent plane influences the name of the month in which its drift brings it closest to the mortal world.

The seven days of the week, in order, are Hrunkear, Tvakear, Trikear, Fottkear, Fiffkear, Aokear, and Morkear.

The common calendar of Aelonis tracks the years since the founding of the dragon Empire of Koth, using the abbreviation AK. The initial domination of Aelonis ended on 8 Hrodis 13 AK. The Wailing was unleashed a little under two centuries later on 19 Urlan 201 AK. By default, a new Eldar campaign begins on 1 Lagar 216 AK.

Eldar Months

How to Use a Calendar in Actual Play

Now that our calendars are designed, what can we do with them?

Every D&D session should have a date that it starts on, right? We can use our calendars to track the length of our campaigns. In my campaign compendium, I always note that start date of the session in-world. It’s a great way to see how long a campaign has been going!

Going a bit further, we could have NPCs casually mention the month or date in conversation. In real life, we do it all the time. That dash of flavor is sure to immerse our players deeper into our worlds. Imagine an elf merchant mentioning she expected a shipment of iron to arrive on 1 Yska, but it never came. She could have said she expected a few days or a week ago, but using the date adds a perfect amount of realism to the moment.

At the start of every session, we could open up with the date and a brief bit of narration. Doing this consistently familiarizes our players with the name of the months and might encourage them to reference them in actual play.

Some DMs even use a calendar to plot out the major events in their campaign or the plans of a villain. This ensures that our worlds remain alive as the PCs drift away from monumental plot points and into side quests. For example, we might plot out your campaign’s world shaking events on our own custom calendars. On the 20 Lagar, 206 AK, the ritual of the mad mage succeeds. In the evening of 12 Yska, 215 AK, the legendary Rangon’s Comet crosses the sky and lights the northern realms with fire. At noon on the 1 Urlan, 201 AK, the dragon Empire of Koth unleashes forbidden magic upon gnome lands. Especially in a campaign with many moving parts, utilizing a calendar of events helps and with a custom one it becomes easier.

As we play more than one campaign in your world, we might refer to past events or years using the date. The year my old group defeated the tyrannical liches of a fractured nation is named the Year of Dread’s Passing. Or the year my previous adventuring band halted Yeenoghu from entering the mortal world is called the Year of the Yeenoghu’s Denial. Or perhaps people refer to the time when a squad of heroes drove a draconic cult from the realm as Day of Obsidian's Cracking. With a calendar, we'll easily be able to track all these events of our worlds' past with ease. Referencing them will surely excite current players whether or not they were a part of the world’s past in some way; it hints that their actions have impact and will be remembered for years to come.

Lessons Learned

Custom calendars are not only an exercise in worldbuilding, but a welcome addition to a Dungeon Master’s repertoire to immerse their players in their world. Take note of what we learned.

• Calendars have a long history in our own world that can be mined for ideas.
• Keep the most familiar and personal elements of Earth’s timekeeping system, items like seconds, minutes, and hours. Customize the rest as you see fit.
• There’s plenty that goes into creating a calendar for our worlds. What are the months named after? Who created the calendar? Why do the years last as long as they do? We don’t need to have an answer for everything—but we should define the basics.
• Calendars carry plenty of weight when it comes to usability. They’re fun to build and can be used to improve our games in many ways.

Until the next encounter, farewell!

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