Suloise Dating, abbreviated SD, is the way the ancient Suloise Imperium counted their years. Today it is used by the Scarlet Brotherhood and possibly other Suel-descended nations that were never part of the Great Kingdom.
The first year of the Common Year calendar was equivalent to 5516 SD, while CY -1 was equivalent to 5515 SD. While the precise significance of Year 1 in the Suloise Dating system is not known in canon, Dragon #241 indicates that the Suel Imperium had been extant for over one thousand years by 1100 SD, making it therefore likely that 1 SD was when the Imperium was founded (p. 47).
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