Mandalorian Dating Systems and Calendars
After spending the whole afternoon developing a dating and calendar system for the Mando-centric fic I’m currently writing, I ended up with not one, but two different systems (and some headcanons about the Galactic Republic dating system).
For simplicity’s sake let’s assume the Galactic Republic uses predominantly the year of the Ruusan Reformation epoch for their dating system. The year 0 ARR (After the Ruusan Reformation) corresponds to the year 1000 BBY (Before the Battle of Yavin). The calendar system is the Coruscant-based standard one with the year’s length being 368 days. The date notation is yyyy.ddd (e.g. 948.126 ARR is the 126th day of the year 948 After the Ruusan Reformation).
Mandalore was founded in 9991 BBY so they began their dating system with the Founding of Mandalore (FoM). I headcanon the Taungs decided to keep their calendar system unchanged after leaving Coruscant and eventually colonizing Mandalore which means a Mandalorian year has 368 days just like the Galactic Republic one. Unlike the latter, however, the Mandalorian year begins 67 days later (e.g. 9253.1 FoM, the first day of the year 9253 since the Founding of Mandalore would be 262.68 ARR).
Why a 67 days discrepancy? It would be weirder if they were synchronised.
Since I cannot imagine the New Mandalorians would want to use the FoM as their dating system, and considering the movement began after the Mandalorian Excision, the New Mandalorian Calendar (NMC) system will use the Excision (738 BBY, 262 ARR, 9253 FoM) as year 0. The length of the year and the New Year are identical to the traditional Mandalorian calendar system.
So basically
0 BBY = 9991 FoM = 738 NMC = 1000 ARR
Cheat sheet:
BBY: Before the Battle of Yavin
FoM: Foundation of Mandalore
NMC: New Mandalorian Calendar
ARR: After the Ruusan Reformation
Some notable dates of Legend/Disney canon events in the various dating systems:
934 ARR (9925 FoM, 672 NMC, 66 BBY) Jango Fett is born
940 ARR (9931 FoM, 678 NMC, 60 BBY) the Mandalorian Civil War begins
943 ARR (9934 FoM, 681 NMC, 57 BBY) Obi-wan Kenobi is born
948 ARR (9939 FoM, 686 NMC, 52 BBY) the Battle of Korda VI is fought; Sheev Palpatine is elected Senator
955 ARR (9946 FoM, 693 NMC, 45 BBY) Obi-wan Kenobi becomes Master Jinn’s padawan
956 ARR (9947 FoM, 694 NMC, 44 BBY) the Battle of Galidraan is fought; the Stark Hyperspace War begins
959 ARR (9950 FoM, 697 NMC, 41 BBY) Anakin Skywalker is born
961 ARR (9952 FoM, 699 NMC, 39 BBY) Anakin and Shmi Skywalker are sold to Gardulla and begin their lives on Tatooine




















