The Decian Empire

The Decian Empire is a mythical kingdom that was once said to span the entire continent of Amerak. The city state of Decia was said to have existed "somewhere on the other side of the Temekis Desert" before sinking into the ocean after angering the gods.
Little is known of the Decian Empire, if indeed it (or something similar) ever existed. In historical times, it has mostly been used as a political tool by kingdoms seeking subjugate their neighbors under the flag of a "reunited" Decia. In particular, during the Resurrection War both kingdoms of Nur-kaliph and Sur-Kaliph sought to lay claim as inheritors of Decia, arguing that the once-unified territory of Kaliph was the primary successor state of the fabled empire on the Tranquil Coast. The claims of both conflicted with a large army of barbarian invaders that arrived from the eastern desert calling themselves the Mercians, and claiming they were the true inheritors of Decia. While Decia may be nothing more than a legend, most scholars generally agree that the entirety of the Tranquil Coast was in fact unified under the banner of the Kaliph. Whether Kaliph had ever been part of a larger, earlier empire is unknown.