The subject of this article has not yet been localised outside of Japan by Konami. Please remember that these romanisations are non-canon.
Yuga was the homeland of the Yuga people that existed before the attacks of the Terrus Firma. The Yuga homeland was known to be the birthplace of both sorcery and the art of ninjitsu. As Yuga was located far from the Holy Empire of Ionia and the effects of its Barrier, it was destroyed by the Terrus Firma many centuries ago.
Since then, the remaining Yuga people have spread across the Empire.