Characterizing Your World

The most labor intensive part of creating a fully fleshed out world is easily the creation of characters to fill it with. Some worlds, like Nintendos' Hyrule in Legend of Zelda: Breath of the Wild succeed with a sparse cast, while others like the Marvel Cinematic Universe thrive on their vast and expanding cast.
Putting characters in your world can come in two flavors: Characters whose creation ingorms the world, and Characters who are informed by the world. We will take a look at the latter in this article, and the former in the next.

Characters Informed by the World

Looking at locations and settlements you have created, ask your self, who lives here? How is their existence defined by what has already been made before them? Do other characters effect their existance? What about items and background events?
This style of character creation is nice because it allows you to come back and analyze how new creations effect old. By connecting new characters to already existing parts, you also avoid World Sprawl. Sure, a new small thing can be added here or there, but this keeps you from having to slam a new organization or species into your world.
Another enjoyable boon is in naming a character. If the local culture is already figured out, then naming this person, as well as knowing their place among others, is made simpler than trying to name a character with no existing connections. Keeping organizations and settlements seemingly strong as far as their community is concerened also gets easier. The lack of options as you choose your connections creates a tightly interwoven web of characters, places, groups that just isn't possible when the character is a blank slate at the very beginning.
Luckily, Informed Creation is not kept solely to Characters.You can use Informed Creation for designing animals, laws, sports, technology and even buildings! Just decide as many connections as you need to make the decision of the final project.

Cooper's Toolbox

A bit of a challenge this time. Take a location, item, species, and organization in your world and create a character whose existence is informed by these other five things. You can add more connections, but these are usual standards of connections for protagonists and antagonists alike.