Calendars and dates

Why the codex has calendars

Some facts are only true for a while. A captain holds a rank until she's promoted; a city stands until it falls; a character is twelve in one book and forty in the next. To say when a fact applies, the codex needs a way to write dates—and your world may not count years the way ours does. So each universe has at least one calendar, and a fact can say "from here, to there" on it.

If your books are set in the ordinary world, you can leave all of this alone. Every universe starts with a Gregorian calendar, and that's the one you'll be offered.

Where it lives

In the codex, click Setup at the top right. The rail that opens has a Calendar system card. The default calendar is already there, named Gregorian; rename it if your story calls it something else, and there's a table beneath, How other worlds would write theirs, showing how a Star Wars, Star Trek, Tolkien, Dune or Westeros calendar would be set up, in case you'd like to borrow one.

Screenshot: the codex's Setup rail with the Calendar system card open, showing the default calendar named Gregorian and, beneath it, the table How other worlds would write theirs.

What a calendar needs

Calendar name—what you see. Gregorian, Stellar date, Imperial reckoning.

Dates are written as—how you'll type a date for this calendar. Five ways:

a year, with an era if any: 2024 · 68 CE · 44 BC · 4 ABY. The usual choice.
month.day.year: 11.04.8927. (Aeon 14's stellar dates are written this way.)
day.month.year: 04.11.8927.
year-month-day: 2024-05-14.
year.day-of-year: 8927.308.

For the three with a month and a day, you can separate the parts with a dot, a slash or a dash—whichever you type is fine.

Before the zero point—if your calendar has dates before its year one, the word that marks them: BCE, BC, BBY, Before Landing. Then "12 BCE" is understood as twelve years before. Leave it empty for a calendar that only counts forward (a stardate, say).

The calendar also has a short key (shown when there's more than one calendar). It's what facts point at behind the scenes and doesn't change once set; the name is yours to change whenever you like.

Writing a date

Wherever the codex asks for a date—a fact's from and to, when an entry exists—type it the way the calendar says. The codex keeps exactly what you typed and shows it back the same way; underneath, it works out an order so it knows that 68 CE comes before 70 CE and 2 BCE before 1 CE. A bare year is always accepted, whatever the calendar's style, so "8927" works on a month.day.year calendar when you don't know the day.

If something can't be read, the box tells you and shows the style the calendar expects. (And yes: historians skipped year zero, and so does the codex—1 BCE is followed by 1 CE.)

A second calendar

Science fiction and fantasy often need two: the world's own reckoning and, thanks to time travel or prequels, the one the readers know. Click Add a second calendar in the Calendar system card, give it a name and a style, and it joins the first. Every fact's when then says which calendar it's on, and an entry can exist on more than one—a character might have a stellar-date birth and a Gregorian one.

One calendar is marked primary: it's the one offered first. Make primary changes which.

Where dates show up

On facts: Add book, series, or date-specific information lets a fact run from one date to another on a calendar.
On entries: each entry can say when it exists on each calendar, or Applies to all dates. An entry that doesn't exist yet at the moment you're writing in won't show up when the codex is framed to that moment.
In Working in: for each calendar in use, choose Any time, or At… a date, or Not on this calendar, and the whole codex shows the world as it was then.

Those three are the subject of What's true when and where.