The Er'ther Lands, home of the former Terrestrial Kingdom, are what constitute the world in which Tales of Destiny and Tales of Destiny 2 take place, while the planet itself is unnamed. The primary source of energy in this world derives from an ancient mineral resource known as Lens. Business, politics, and religion revolve around the exploitation of this resource, leading to conflicts among the nations of the world throughout history. Lens is said to come from the fragments of an ancient meteor that crashed into the planet's surface prior to the split of the Er'ther and Aeth'er races.
The modern world is divided into five distinct regions: Seinegald, Phandaria, Calvalese, Fitzgald, and Aquaveil. The planet's central continent is its largest, housing the two largest kingdoms of the world, Seinegald and Phandaria, both of which are involved in frequent border conflicts with each other. Other countries are mostly neutral in this affair, but they have been known to favor one or the other due to past interactions with their governments. In Tales of Destiny 2, as a result of the Belcrant disaster, several craters can be found scattered across the landmasses, though the terrain itself has mostly recovered.
The majority of the planet, save its oceans, is claimed territory, though a large chain of islands in the southeastern hemisphere is unclaimed and lacks any settlements or notable locations. Green fields and occasional mountains are familiar to the regions of Seinegald, Fitzgald, and Aquaveil, while Phandaria and Calvalese drastically contrast these regions and each other. Phandaria is naturally enveloped in a winter-like state, with a prominent mountain ridge in its northern region, and Calvalese is desert, mountain-heavy region with rugged terrain and lava-filled rivers created by active volcanoes, spurring harsh living conditions.
Around 1,000 years prior to the events of Tales of Destiny, a large, Lens-infused comet collided with the planet, enveloping the sky with a cloak of dust clouds. This, in turn, plunged the world into an ice age that threatened humankind. However, with the mysterious and powerful Lens of the comet, the crisis was averted. The people used the Lens to create and power a massive floating continent known as the Aethersphere, which hovered above the Er'ther Lands. The Aethersphere was home to the Aeth'er race, while the the Er'ther Lands were inhabited by the Er'ther race. The two entities later engaged in what later become known as the Aeth'er Wars. The Aeth'er race, led by the Aetherian ruler Kronos, possessed a large and powerful, sword-shaped superweapon known as Belcrant, which protruded from beneath their aeropolis capital, Dycroft.
Using Belcrant and their superior technology, the Aetherians struck down all who opposed them until a group of Aetherian scientists, disgusted with their people's elitist behavior, descended to the Er'ther Lands and developed sentient swords known as Swordians that ultimately led to the defeat of the Aetherians. As a result of the war, the Aethersphere and its aerial cities were destroyed and plunged into the depths of the ocean, and its populace was exiled to the desert region of Calvalese. This left the Er'thers as the only sentient race inhabiting most of the planet. The modern population of people are descendants of the Er'ther race, and the Aeth'er race has long been forgotten by the common people, though they comprise nearly the entirety of Calvalese's population. When Hugo Gilchrist of Seinegald's Oberon Corporation uses the Eye of Atamoni, a large and extremely powerful Lens, to revive the Aethersphere, a familiar threat spawns once again.