Characters are like the Goddess Athena; they so often spring fully-formed from the heads of their creators. After all, it is an enormous commitment to detail every part of a character’s life from birth to the start of the adventure! Some systems recommend it (Burning Wheel), and some GMs like to do it to build context, but it is not always necessary.

So much of character creation revolves around creating fast and easy context to inform gameplay, without taking too long. Some groups (mine among them) have seen immense success with laying out bare bones and then filling in more details if they become relevant.
Examples:
“This place reminds me of a shop I used to steal from when I was a child.”
“You don’t seem to trust the Halfling. What makes you feel that way?”
“The Lost Arches… the last time I passed through here, I was thirty years younger and still thought I could change the world…”

However, one oft-overlooked way of building context is to simply Give the Character a Family.
Families serve not only as plot points which can be brought into play, but they give the character a grounding which is more personal and permanent than jobs or residences. Families are often (but not always) settled, and in most cases are contacts which can be used for emotional support. Even just creating NPCs who expect things of the character which may not align with the primary story can create interesting drama.
For example, not only does having a character’s family living in the city which is in danger create context and tension, they also know about the character’s childhood and can create a window into their early life and pre-adventure experiences.
Examples:
“Can we avoid the market? My dad works his shop there, and whenever I see him he gets on my back about taking over the business…”
“Hey no worries, we can stay at my sister’s place! She’s always had room for us before!” Little do they know, the sister is now married and is less-than-thrilled…
“My grandson, your grandfather and I worry about you. We always worry about whether you will come home when you set out. When will you settle down?”
And twists can always be imposed on this, such as uncaring family dynamics, traveling families who might show up at other locations, and families who have drama and adventures on their own, just like the characters! It’s almost as though NPCs have lives outside of the players!
