Okay, I'll give some basic stuff. :>

She's from an old, small town, nestled away somewhere. Perhaps an island not on a route. The town was founded by a warrior group, and those roots had given rise to a focus on discipline through martial training. If one can be strong and fit of body, one can be strong and fit of mind. It was only natural that fighting-type pokemon became popular on the island.

On her 14th birthday, she was given a Torchic and started a Pokemon Journey. Over the next four years, she made her way up to the Hoenn Regional League. After her experience in the League, she released all but six of her pokemon. These were supposedly left behind when she left to become a Ranger two years later.