My players have trouble creating deep backstories for the characters. I have decided to go with that but provide opportunities in-game for filling out the gaps. I’m considering introducing some flashbacks, which I have never done and have no idea how to do. I would also want those stories to have real impact on the game (so that the players feel the story is important).
How do I go about stimulating the players to tell and expand and play out the back stories of the characters?