B.T., the World of Greyhawk setting for Advanced D&D did that with its timeline, too. There's a rich background of political events that unfold not unlike a "Twilight:2000" for a fantasy world (two huge empires unleash terrible weapons and utterly destroy one another, leaving a broken world of imperial city-states peopled by desperate men and women scavenging the ruins for supplies, magic items and so on, hiring themselves out as mercenaries, etc.)
It brought the "game clock" from thousands of years in the past to "Common Year" 576 and left the rest up to the DM...
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