(Metagame, this chronology being made before Owen decided that ponies had human-like lifespans is why magical life extension is a thing.)

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(-372) On 6 Flowers of the 17th regnal year of Star Sparkle, queen of the Eastern Kingdom, ascended the throne of the Western Kingdom, thus becoming queen of all unicorns.

(-299) Thus on 28 Snows of the 90th regnal year of Star Sparkle, queen of all unicorns, did  pass into immortality.

(-298) On 4 Gourds, Fancy Crown, crown prince, hereditary guardian of all legitimate magic, ascended the Horned Throne of the Unicorn Kingdom, aged 151 years, 6 months. Thence he was king of all unicorns.

(-227) Thus on 4 Crafting of the 71st regnal year of Fancy Crown, king of all unicorns, did pass into immortality.

(-227) On 19 Crafting, Twinkle Star, crown princess, hereditary guardian of all legitimate magic,  ascended the Horned Throne of the Unicorn Kingdom, aged 91 years, 2 months, a lunar cycle, 2 days. Thence she was queen of all unicorns. 

(-170) On 1 Gourds, the 57th regnal year of Twinkle Star, she bridled the sun and moon for all unicorns, and brought peace to the world and to pony-kind.

(-160) Thus on 21 Snows of the 67th regnal year of Twinkle Star, queen of all unicorns, moving-coordinator of the sun, turning coordinator of the moon, did pass into immortality. 

(-160) On 20 Grasses, Moon Shine, crown princess, hereditary guardian of all legitimate magic, turning-coordinator of the moon, ascended the Horned Throne of the Unicorn Kingdom, aged 42 years, 8 months, 13 days. Thence she was queen of all unicorns.

(-155) Thus on 17 Rye-Planting of the 5th regnal year of Moon Shine, queen of all unicorns, turning-coordinator of the moon,  did pass into immortality.

(-155) On 1 Crafting, Stargazer, crown princess, hereditary guardian of all legitimate magic, ascended the Horned Throne of the Unicorn Kingdom, aged 35 years, 5 months, a lunar cycle. Thence she was queen of all unicorns.

(-36) Thus on 1 Corn of the 119th regnal year of Stargazer, queen of all unicorns, moving-coordinator of the sun, turning-coordinator of the moon, did pass into immortality.

(-36) On 16 Corn, Golden Comet, crown prince, hereditary guardian of all legitimate magic, moving-coordinator of the sun, ascended the Horned Throne of the Unicorn Kingdom, aged 103 years, 2 months, 6 days. Thence he was king of all unicorns.

(37) Thus on  27 Fruits of the 73rd regnal year of Golden Comet, did pass into immortality.

(37) On 4 Corn of her 37th regnal year, Platinum, crown princess, hereditary guardian of all legitimate magic, queen of Equestria, ascended the Horned Throne of the Unicorn Kingdom, aged 57 years, 10 months, a lunar cycle, 14 days. Thence she was queen of Equestria and the Unicorn Kingdom, and thus the states were united.

(200) Thus on 22 Heat of the 200th regnal year of Platinum, queen of all unicorns, queen of Equestria, did pass into immortality.

(200) On 30 Heat, Silver Swirl, crown princess of Equestria, ascended the united Throne of Equestria, aged 114 years, 2 months, 6 days. Thence she was queen of Equestria.

(244) Thus on 18 Rains of the 44th regnal year of Silver Swirl, queen of Equestria, did pass into immortality.

(244) On 26 Rains, Galaxy, crown prince of Equestria, ascended the throne, aged 67 years, 11 months, 1 day. Thence he was king of Equestria.

(320) Thus on 27 Seeds, Galaxy, king of Equestria, did pass into immortality.

No pony ascended the throne of Equestria for 110 years 7 months a lunar cycle, 8 days.

(430) On 20 Snows, Celestia, princess of Equestria, mover of the sun, aged 203 years, 6 months, and Luna, princess of Equestria, turner of the moon aged 179 years, 4 months, ascended the throne. This was the 430th year of Equestria, the 802nd year of the uniting of the unicorn kingdoms, and 

This stele erected at the order of Celestia, princess regent of Equestria, mover of the sun, in her 10th regnal year, the year of the 600th anniversary of the bridling of the sun, on the occasion of the Summer Sun Celebration in Canterlot, for the purpose of establishing the chronology of the royal line. 

Graven by Chisel Chip, royal engraver.

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