Hot answers tagged campaign-development
Fate Core, and other Fate-based systems, seem to do exactly what you're asking for. Since you're asking specifically about character backgrounds, I'll skip the part about collaborative game-world creation, which is also present in these games, and skip straight to the characters. Chapter 3: Character Creation (FC30) opens with the header "Character Creation ...
Only top voted, non community-wiki answers of a minimum length are eligible