Raised on the border of two nations? Found a knack for the military and spent time in the militia? Where you learned Tionicca from a master that trained the local soldiers?
Or maybe you were raised a Jewel Elf and took much of your parent's upbringing and added it to the tumultuous mix you learned while running the streets of talismonde; hanging out with that girl from Viruelandia who spent a time in a Morvaenian prison before escaping. Her hard lessons were ones you didn't ignore and you've spent time building a gang that guts slavers and Morvaenian's alike.
Either of the above or myriad other combinations are possible and reflected well. Its one of my most favorite parts of AE and sourced hundreds of tales in my personal games.
A key point was understanding the cultural influence significance. It meant that you were either raised in that culture or influenced by it, whether you lived in that land or not. Ever meet someone who was more japanese than the japenese? Who loved their culture to death but lived in the USA?
Think about it.