Xerxes

Xerxes is an ancient country in the Full Metal Alchemist universe. It was here that alchemy and Van Hohenheim have their roots. Hohenheim was a nameless slave, taught reading and basic arithmetic by a strange creature called Homunculus, which he had helped create with his own blood unknowingly. Homonculus eventually convinced the king of Xerxes to build massive irrigation channels, which were actually a massive transmutation circle, in order to gain immortality. Immortality was gained, but only by Homunculus and Hohenheim, who was rendered a living philosopher's stone, a soul confined to a body made of other souls. The cost of this transmutation was the life of every one in Xerxes. Their bodies were later used to create Envy's true form.