He / Him
I had a general concept for a campaign: Vampire Oppressors in a secluded valley. (A remix of Curse of Strahd.) I knew there would be an enslaved peoples, a ruling class, a few other roles. The players made their characters and I filled it in from there.So was this built off the PC races your characters chose and you built up a world they would be connected to, or did they come up with backgrounds that you took and ran with, such as the tiefling-vampire connection?
The original characters were a tortle, a tiefling, an aasimar, and a goliath. I decided tortles were the enslaved and oppressed class, tieflings were the upper class, aasimars became a group of warriors who had passed through long ago, and goliaths were outsiders and very rare.
I filled in the valley with humans and some halflings, because I like halflings.
When the tortle character died, the player rolled up a gnome. We decided gnomes had been forcibly imported as expert artificers and mages.
This is my first time building the races of a campaign world off of player choices, and it's been really fun!