A great thing about creating your own world when developing a homebrewed campaign, is being able to reign in your players just a bit during character creation. Naturally, you want your players to be able to create a character they’d enjoy playing, however, sometimes things get a bit stagnant or repetitive as the same type of character is created time and again. An alternative way to allow for a more dynamic party is have your players create their characters with no backstory (not yet at least) and then, depending on their race, class, profession, level, etc. you can then tell them not only where they were born and the culture they were born into, but also where they might have traveled in order to learn their skills. Then let them fill in their backstory with these new factors.
“How?” you ask, let me show you an example: