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I want to set up a custom calendar with eras

743 words·4 mins
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Use this when your fictional world needs its own date system — alternate-history fork, custom fantasy ages, sci-fi reckonings, anything that doesn’t fit Gregorian dates or one of the four built-in calendars (Middle-earth, Westeros, Star Wars, Generic Fantasy). By the end you’ll have a calendar registered with named eras, optionally scoped to a universe, and you’ll know how to use the resulting date format in person and event frontmatter.

If your universe is Middle-earth, Westeros, or Star Wars, you can skip this — the built-in calendars cover those. A built-in-calendar guide is queued.

What you’ll need
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  • A universe note for the world you’re building, if you want the calendar scoped to a single universe (recommended). See I want to create a fictional universe.
  • An idea of your world’s eras: their names (e.g., “Age of Legends”), abbreviations (e.g., “AoL”), and epoch offsets (the year that anchors each era to the timeline).
  • A choice of a “default era” — the one used when a date string doesn’t specify which.

Steps
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1. Open the calendar settings
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Settings → Charted Roots → Dates & validation → Fictional date systems. Or from the Control Center: Events tab → Actions → Fictional date systems.

Confirm Enable fictional dates is on. Toggling it on also removes the 120-year age cap in the statistics dashboard, so longevity-aware fixtures (elves, vampires) appear correctly.

2. Add a new system
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Click Add in the Fictional date systems section. Fill in:

  • Name — display name (e.g., “Aeons of My World”)
  • ID — auto-generated from the name; customizable
  • Universe — link to your universe note. Optional, but recommended so the calendar only surfaces in date pickers for entities in this universe.

3. Define the eras
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Click + Add era for each era. For each one:

  • Name — full era name (e.g., “Age of Legends”)
  • Abbrev — short form used in dates (e.g., “AoL”)
  • Epoch — year offset from the reference point. 0 for your primary/reference era. Negative numbers for earlier eras (e.g., a “Second Age” with epoch -3441 means SA 1 falls 3441 years before AoL 1). Positive numbers for later eras.
  • Direction — Forward (years count up, like AD) or Backward (years count down, like BC).

4. Pick a default era
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The dropdown sets which era is assumed when a date string omits an era prefix. Usually the “current” or most-used era in your storytelling.

5. Save
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The system is now active. Date pickers in event-creation modals will offer it; the date parser will recognize era abbreviations from this calendar in person and event frontmatter.

6. Use the dates in frontmatter
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The format is {abbreviation} {year} (case-insensitive):

---
cr_type: person
name: A Character
universe: my-world
born: "AoL 2890"
died: "AoL 2961"
---
---
cr_type: event
title: A Major Battle
event_type: military
date: "AoL 2941"
---

7. Verify
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Test parsing in Settings: enter a date like AoL 2941 in the Test date parsing input. Green = parsed correctly with era name + year + canonical year for sorting. Red = error message explaining what didn’t match.

Calendar View rendering a fictional date system: events appear with their universe-specific date format

Variations
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  • Use a built-in calendar instead. If your world is Middle-earth, Westeros, Star Wars, or maps to the Generic Fantasy ages, skip the custom setup — a dedicated built-in-calendar guide is queued. The four built-ins are enabled by default; toggle Show built-in systems off to hide ones you don’t use.
  • Calendarium plugin integration. If you already maintain calendars in the Calendarium plugin, enable the integration under Settings → Charted Roots → Advanced → Integrations → set Integration mode to “Read-only (import calendars)”. Calendarium calendars then appear alongside built-in and custom systems in date pickers. Read-only — Charted Roots doesn’t modify the Calendarium definitions.
  • No universe link. Skip the universe field if the calendar should apply globally. Useful if multiple universes share the same date system.
  • Editing later. Custom systems can be edited (pencil icon) or deleted (trash icon) anytime. Built-in systems can only be hidden, not modified.

Related guides#

Reference
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