Notes on the Mortal calendar------
It is not necessary to remember these details as you read the story; this is intended only to provide background on the dates included in family trees, timelines, character backstories, etc.
Solstices & equinoxes are determined as we would, each season encompassing exactly three months.
Months are "moon's turns" (28 days long).
Half a moon's turn is a "fortnight" (14 days) & half of such is simply "half a fortnight" (7 days).
Birthdays are "namedays."
What we would call Christmas is "the Yule."
Days of the fortnight are not named, & individual dates are not recorded.
Modern history is broken down into three 1,000-year eras: the Shadow Era (S.E.), the Dawning Era (D.E.) and the Era of Light (E.L./current). The E.L. is broken down into four ages: the Frost (Fro.) Age ("First Age"), the Glass (Gla.) Age ("Second Age"), the Crystal (Cry.) Age ("Third Age") & the Diamond (Dia.) Age ("Fourth/current Age"). Ages are broken into simply numbered centuries (1st-10th/C1-C10). Each decade is known by the name of a creature of myth: dragon, siren, wyvern, phoenix, cerberus, mermaid, unicorn, leviathan, behemoth & kraken (in that order, each century). Each year of each decade is known by a color: crimson, indigo, golden, sunshine, violet, sunset, emerald, silver, sapphire & platinum (in that order, each decade). Years are broken down into seasons: winter (wi.), spring (sp.), summer (su.) and autumn (au.)
Formally, dates are recorded thus: [Season] in the Year of the [Color Creature], Century [#], Age of [Age]. Example: the time in which the story begins is Spring in the Year of the Indigo Phoenix, Century One, Age of Diamonds (Abbreviated Sp., Indigo Phoenix, C1, Dia.
To simplify, each year has a number indicating the age of modern history (M.H., or what we call the current era/C.E. (similar to our anno Domini/A.D.)). Example: The year in which this story begins is M.H.3031, or simply 3031. So, informally, dates are recorded thus: [month (“moon's turn”) #][season abbrev.][year]. Example: The time in which the story begins is 3sp.3031 (indicating the 3rd moon's turn of spring in the year 3031, which is the same as Spring in the Year of the Indigo Phoenix, Century One, Age of Diamonds, as stated above).
Namedays are celebrated during the season in which the person was born, on approximately the same day (chosen by the family at birth), each year. Example: Princess Clío’s nameday is the 17th day of the 2nd month of spring. Her birthdate is 2sp.3011, or Spring in the Year of the Indigo Siren, Century 1, Age of Diamonds. This date format: [SPINDSIRC1DIA] is used in formal record-keeping only.
Note on names: Female highborn, particularly royals, are traditionally given a unique first name, followed by their mother's name and their grandmother's name, respectively. This is intended to leave no question as to the lineage of the child, something that is very important in the western world. Male highborn are named the same way: a first name, followed by their father's name, then their grandfather's; suffix (II, VI, etc.) are placed directly after the first name. When women marry, they place their husband's surname after their own.
Notes on the premodern Mortal calendar------
Recorded history is broken down into 1,000-year ages. Pre-modern history (P.M.H.--known as the Dawning Era) encompassed five ages: the Age of the Moon (MO), the Age of the Heavens (HE), the Age of the Earth (EA), the Age of the Sun (SU) & the Age of the Stars (ST).
It is currently early in the modern Age of Diamonds, or Fourth Age. (see above)
History predating P.M.H. 5000 is known as the Shadow Era, and little is known of it.
Dates were recorded differently in premodern history, than they are in modern history. Exact dates to the month and day were considered irrelevant and only the year was recorded. Example: Silvana Starshine, first empress of the Faradeshi Empire, was declared (coronated) in the 39th year of the eighth century of the Age of the Sun. That date is indicated by how many years it was ("39") into the current century (C8, "08") and age (Sun, abbreviated with the first two letters of its name, "SU"), noted thus: 3908SU. Empress Silvana is estimated to have been declared on the 21st day of the first month of autumn (recorded today as =1au.1738p. The “=” is used to indicate the date is an estimation or equivalent; the “p” indicates the date fell during premodern history.)