The Old Empire of Ghis, and New Ghis
The first empire the world remembers, with harpy banners and legions of slave soldiers, razed and salted by dragons five thousand years ago.
The fuller tale
Old Ghis was ancient when Valyria was a country of shepherds: brick cities, disciplined legions, and the slavery that every civilisation on that side of the world learned from it. Five wars decided which of them would rule the east, and the Ghiscari lost all five. In the last of them the Valyrians burned the capital, threw down its walls and sowed the fields with salt and skulls, which is thorough even by the standards of this history.
The culture did not die with the city. Its colonies on Slaver's Bay carried on speaking a bastard Valyrian, wearing the tokar, and selling people, and the little island of New Ghis rebuilt the legions on a smaller scale. Every Ghiscari city since has claimed the empire's descent and none of them has come close to the empire's reach.
The ground they held
What became of it — if an ending is written, it is here. Spoilers.
The chronicle records no ending here — or none the maesters have set down.