I don't know if there was a war but this is what I've read
Lt. Surge, formally in the armed forces, has become a Pokémon trainer who relies on pure power. Believing that unevolved Pokémon are weak, Lt. Surge evolves his Pokémon literally as soon as possible. An arrogant man, Lt. Surge constantly berates any trainer that is unable to beat him, especially if they are unable to defeat him. However, despite this, when a trainer does manage to defeat him in battle, he does gain respect for them and treats them as such.