The Pokémon World is the main planet in the Pokémon universe, the home of both humans and Pokémon.
Long ago, the mystical Pokémon known as Arceus first came into being, creating the entire universe. It proceeded to create Dialga, Palkia, and Giratina, to control time and space, and Giratina was banished to another dimension. Mew, containing the DNA of all future Pokémon, also came into existance.
The Hoennian weather trio of Groudon, Kyogre, and Rayquaza were formed after this. Groudon created landmass while Kyogre made the seas. An encounter between the two turned them into rivals, and an all out battle was only prevented by the appearance of Rayquaza. The two rivals went to sleep, while Rayquaza returned to its home in the ozone layer.
Humans eventually separated from Pokémon after prehistoric times, and expanded to cover the entire world. The first writing systems came into existance roughly 1,500 years before the events of Red/Blue. Kingdoms were formed that either dissolved over time, or evolved into the current countries.
In 1914, 190 years before Red/Blue, Kanto was the dominant power in the world. Noticing that Johto was also on the rise in power. After a secret plot to stop this rise was uncovered, the world was divided into factions, and The Great War started.
In 1939, 160 years before Red/Blue, the world population was roughly 2.3 billion humans and an unknown amount of various Pokémon. The start of the next war once again encompassed the world in conflict, and a severe population decrease is likely.
- Sevii Islands
Unova was originally neutral in the war, and contributed to both fronts. The first battle of the new war occurred off the coast of Undella Town, and determined the ultimate fate of Unova. Kanto forces, arriving first, held back advancing Johto troops, effectively winning Unova.
The Orange Islands and Almia have expressed their neutrality in the war, and refuse to contribute to either Johto or Kanto.