flag of Equestrian Empire

"...At its height under Empress Maiestas Maximus (Majesty the Great), the Equestrian Empire of the Classical Era stretched throughout much of the known world, its power unchallenged militarily and economically by any of its neighbors, client states and rivals...

... The empire's territories stretched beyond the entirety of Equestrian subcontinent; across the Median Sea to the west, the empire conquered the Cassiteridian isle and the Taurus Peninsula, as well as the south and western parts of Griffonnia, ruling populations of deer, minotaurs, griffons and non-Equestrian ponies. To the south-east of Equestria, pass the Great Channel connecting the Median Sea to the Shining Sea and separating Equestria from the badlands, old Anubia's crops fed the ponies of Equestria, grown upon a fertile soil along the banks of the Iteru river, while the borders stretched across the coasts of Zebrica, and deep into desert lands where modern Maretonia and Saddle Arabia now stood. Everywhere the legionnaires of Equestria had marched, the land was placed under the banner of the Empire...

...And at it's heart, stood the city of Hearth, Equestria's first capital, now lost to the ages; accounts told of a city with great public buildings of white alabaster crusted with jewels, of temples decorated with marble columns trimmed with gold, of great markets filled with goods that flow from every corner of the empire and from foreign lands as far away as the land of the Qilin in the Orient; its walls, gates and streets guarded imposing statues of equestrian heroes mythical and real, and emperors or empresses of dynasties past and present. Aqueducts as long as the rivers they are linked to supplied water to the capital and its populace, as well as watering a countryside of farmland and ordered nature tamed by earthpony magic, dotted by estates of wealthy nobles and retired legionnaires...

... In many locales of modern Equestria, traces of the old Empire could be found: Where Canterlot now occupies, upon a cliff side of Avalon mountain, once stood the domed complex of the Conlegium, Equestria's great school and library of magic and philosophy, a hub of knowledge of both the mundane and the arcane. Under the cloud city of Las Pegasus, or 'Pegasopolis' in the Classical Era, was the Castra Arctos, 'Hurricane's Camp', one of the greatest fortress in the ancient world, where new legionnaires and generals were trained to defend and conquer for the empire. Outside the city of Hearth itself, it was said, stood Palatio Somniatis, the 'Dream Palace', the opulent home and office of the Emperors and Empresses, dwarfed in scale only by the ziggurat structure of the Mausoleum, which was the final resting place of the Founders of Equestria, the Empire's chief pantheon of deified gods, and that of past Emperors and Empresses who had passed into the next world. Atop the Mausoleum, the flames of Hearth's Warming Eve burns on a massive altar daily, symbolizing the friendship and unity of the empire and its people, and the ever-shining reminder of Equestria's might and glory, one remembered long even after the empire's fall ..."

--- Excerpts from Imperium: An illustrated guide to the lost empire of Classical Equestria, Chronicle Publishing Inc, Manehatten.