jgsugden
Legend
They had their backstories from the beginning. Look at the comic books that chronicle their Vox Machina origins. The early story was built out of their backstories.also... the CR cast even say they are performing on the show. They didn't have so elaborate backstories and deep personal relations before the show. Saying they are performing is not saying they are fake, or not being honest in their portrayal of the characters or the game....
This is how Matt operates now, and historically. It is how a good number of DMs operate. You get back story, Then you weave it into your stories as you go forward. This allows you to tell a long story that unfolds over several chapters. The backstory of each character folds into those early stories.