Wasteland 3 companions: who can you recruit?

Where can you find the Wasteland 3 companions? Knowing the locations of all the recruitable companions in the latest Wasteland game is imperative to survival, not only do they come with some pretty tasty pre-equipped gear and skills, but they can also massively impact the story and your time in Colorado.
If you're already a little way into Wasteland 3, you've probably been introduced to companions and rangers. If not, you'll be able to recruit people once you finish the initial tutorial and arrive at Ranger HQ. Rangers and companions differ slightly, in that companions are people you find around Colorado and are involved in a mission or the main story in some way. They all have a rich backstory and their own reasons for wanting to join your squad, along with specific attributes they can bring to the party.
Please note, this guide does contain minor spoilers, so if you want to keep everything a surprise then you've been warned. Here are all the recruitable companions in Wasteland 3, along with their proficiencies and where you find them on the map.
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