Five Reasons for a Calendar in Your Game

Over the course of many Dungeons and Dragons campaigns, I've often, but not always, used a calendar to track the progress of the campaign. It can seem like a lot of work with little payoff, but that doesn't have to be the case. If done correctly, you can keep the workload to a fair balance, and the payoffs can be great.

So, here are five reasons you should be using a calendar to track your campaign

1. Session Notes 
• A campaign calendar can be a great place to track session notes. By simply tagging the notes to the month and day of the event, you know what the heroes have been up to and when things happened. For mundane tasks, like fast travel, I just mark the start and end dates of the travel, where they left from and where they arrived.
  
• Back in previous editions when characters trained to gain a new level and would level up at different experience point values, I used the calendar to track who was training and who was free and sometimes could squeeze in a short adventure or side quest for the available characters.
2. Track Campaign Events/Tracking Multiple Campaigns
   
• Similar to Session Notes, I use the campaign calendar to help track key events in the game. This can be anything from when they met a recurring NPC, or for an upcoming event. 
• In one of my current Dragonlance games, one of the heroes is a squire and his upcoming knighting ceremony has been a planned event, including him going on a quest to prove his worth.
• Additionally, if you're running multiple campaigns in the same setting (or same city as I'm doing), tracking what each group is doing is a great way to add verisimilitude to the game. I often have the different parties meeting the same NPCs and hearing about each other in passing (someday I'd like to get both groups in the same adventure, but scheduling would be a nightmare)
  
3. Holidays and other Fixed Points in Time
• One obvious use for a calendar is to mark fixed points in time. The date of a holiday or key anniversary (like the end of the War of the Lance) are great ways to build celebrations and adventures tied into the event. 
• In my current game, one of the local pubs hired the heroes to retrieve rare ingredients for a mead they wanted to brew for the Yule celebration months in the future. Later the heroes were able to come back and sample the special mead months after the original quest had been completed.
  
4. Passing of Time, Seasons, and Weather
• Since the Ansalonial calendar has 12 months and the seasons line up with what we experience in North America, it's easy for me to use my calendar and keep the players up to date as to the equivalent month and weather conditions depending on where they are.
  
• Additionally, thanks to an extensive list of holidays in the Dragonlance setting, I have a ready list of large events to use for celebrations, side quests and other purposes.
5. Plotting Events
• Do you have a BBEG with a huge master plan going on? With a calendar, not only can you plot out the steps and events it takes for your Big Bad enact their plan, but you can plot out how long each part takes. This allows you to determine where the heroes might be crossing paths with those events, minions, etc as well as what happens if the heroes don't take action and the BBEG moves one step closer to their goal.
6. The Three Moons (Bonus Reasons for Dragonlance DMs)
   
• In Dragonlance, the moons have special game play purposes and depending on your player's characters, can be very important, or may just be background flavor.
  
• All (or most if you have a flexible DM) arcane casters on Krynn draw their power through one of three moons, related to your hero's alignment (good, neutral, evil). Similarly, casters get benefits or penalties if their patron moon is full, or new and they can gain additional benefits if two or more moons are aligned together. Therefore in Dragonlance it can be very important to know where a spell caster's patron moon is in terms of its cycle (each moon has a different monthly period) and if there are any other moons in alignment.
• For the custom calendar I created, I added fields to track each moon's position and note any alignments. This allows me to set up adventures where the evil spell caster is waiting for the moons to be in a certain alignment to maximize their power, or minimize the power of their enemies.
• Even if you don't need to track the moons for game purposes, knowing their position can add color to nighttime scenes. Each moon has a different color, and depending which one(s) is full and which are wanning, there might be a silver sheen on the water, or a blood pallor over the city.

Hopefully this list has given you some thoughts on why you might want to include a calendar in your campaigns and ways to keep it as one of your DM tools.