Use of Pokémon in the war

The use of Pokémon in battle has only been possible since the invention of the Pokéball, and is a relatively new phenomenon, though it has become almost universal in the years since.

Previous warfare
All automated weaponry was disabled by an unknown phenomenon (in actuality, the psychic legendary Mew) on the 18th of May, 1910. This effectively ended The Great War and modern warfare as it was then known. However, while hostilities had officially ceased, most countries kept sections of their military intact, replacing guns and bombs with more medieval weaponry such as bows and swords. However, it was not until the Pokéball was invented that either side had the means to wage a new large-scale war.

Pokémon taming and the invention of the Pokéball
Both sides made several attempts to harness the power of Pokémon for military use prior to the Pokéball's invention.

Early Pokémon initiatives
With the invention of the Pokéball on the 6th of January 1937, both sides quickly hurried to make use of the new technology.

Johto
As the inventors of the technology, Johto had an initial advantage over their counterparts in Kanto.

Kanto
Ironically, one of the first proponents of the use of Pokémon in the military was future-Rogue leader Jane Delancy, who was promoted to Brigadier-General following the Pokéball's invention and charged with the responsibility of facilitating the army's transition into the pokemon era. The most prominent initial attempt to train soldiers in the use of Pokémon by Kanto was the Pokémon-Human Integration Program; known members of the program include Malcolm Alvand and future Kanto Minister of Defence Dao Nguyen.