In the Wide World, a standard calendar has been in universal use for over 1000 years. The years are numbered as “Modern Year” dating from the Astrological Conclave of Grahblox. The campaign begins in Modern Year 1195.

There are 12 months in each year, which correspond to the 12 signs of the Zodiac:

Aries (spring 1)
Taurus (spring 2)
Gemini (spring 3)

Cancer (summer 1)
Leo (summer 2)
Virgo (summer 3)

Libra (fall 1)
Scorpio (fall 2)
Sagittarius (fall 3)

Capricorn (winter 1)
Aquarius (winter 2)
Pisces (winter 3)

Each of the months is 30 days long. The New Moon is on the first and the full moon is on the 15th of each month.