Training Pokémon has been a tradition for as long as anyone can remember. As a matter of fact, it's a cultural norm. Once a person reached the age of ten they would be gifted a 'Starter' Pokémon. And then would leave home to embark on a journey of self-discovery, joy, pain, remorse, each journey it's very own, the one constant was at the end of each journey the one that embarked upon it was no longer the young kid who left home all bright eyed and excited. Now older, wiser, different, with a set of values and a view on the world, each Pokémon trainers Journey was a right of passage to the next stage of their life. Training is good for the world, for the region... but Pokémon trainers are a dying race.
The Pokémon league has raised the age of beginning trainers to sixteen. And any trainer out in the field who was not sixteen at the time of this law change was not grandfathered in, and was to head home immediately. This brought the training population to a crawl. As each year passed no new trainers were entering the Pokémon training world, and those who had their journeys interrupted either gave up or were very few in number, the training population is smaller than it has been in decades.
People started to fear trainers and their companions, their Pokémon. People barely go outside anymore. Pokémon gym leaders and league officials aren't considered political leaders or community role models anymore... and it's all because Hoenn was divided by a bloody Civil War.
There has always been conflict, it's almost human nature to have some negativity within them. Hoenn has been no exception, the country was rocketed with the 'Rayquazza Event'. By Team Magma and Team Aqua. Hoenn is no stranger to conflict... but a civil war was something no one wanted to happen.
Each region has a police force and a military, its only natural. And that being said, it's obvious both of these government branches utilize Pokémon alongside the police officers and soldiers. Some people hate the concept of training, think it's unfair to the Pokémon, cruel and harsh on the trainer. These people wanted to do something about it. Release Pokémon, abolish training, the Pokémon league. These people want to let the country's youth focus on schooling and jobs instead of Pokémon training. Each person has that choice to begin with, not all partake on a journey, it's not for everyone, but no one has tried to abolish it.
It was only a matter of time before the position of neutrality vanished from these people with such radical ideals and they took up arms, if words wouldn't work, rifles and brute force would. It started out as a few pocket groups of 'Rebels'. Terrorists many called them. But with each Pokémon center bombing. With each trainer gone missing only to be found dead days later way off the training routes... more and more people started to worry... and more and more people started joining these rebels, and they soon had a large following.
It was never really declared when the war started, but eventually, an imaginary line was drawn through Hoenn, separating the Pro-Trainers from the Anti-Trainers. The Eastern Army and the Western Army.
In some parts of the west, the armies presence isn't as strong, and in almost all parts of the west, training continues, albeit very minimally, and with many looks of disgust. Both armies are focusing on each other, and have basically decided to let trainers be while they can... although the risks of being a trainer have escalated to a point where the age requirement was put in place.
Trainers are feared, the countries divided and at war with itself, and people and Pokémon alike are being caught in the crossfire... eventually, everyone who's trying to stay out of the conflict will have to chose a side, and all hopes of neutrality within the region will vanish.
This is the story of how the Hoenn region died.