This is a simple override mod that restores custom backgrounds created by Larian to the origin characters that were eventually cut but remain in the game files. If you pick an Origin character in the character creator, you will have the background from the start. Otherwise when you first meet or recruit a companion they will have an empty background field initially. Save and reload for the background to appear.

This is a very simple mod that has a lot of room for improvement. If a better Modder comes along and builds onto it I am happy to take this down in favor of that. I just made it for my own personal game and thought someone else might like to use it.

I originally got the idea from Plus Backgrounds, which is how I learned these cut backgrounds exist in the first place, but that mod allows you to pick them using your Tav, and doesn't assign them to their actual intended characters. Mine does the opposite; each character will get their intended background, and you won't be able to pick those backgrounds other than by playing those characters. I didn't use any files from Plus Background though, started from scratch.

IMPORTANT: using this mod means only your Tav/Durge will earn inspiration points. I suggest using FrozenLayer's No Inspiration Point Cap mod to compensate for that, until someone better than me fixes the issue. If you pick an Origin character in character creation, then there will be no inspiration at all. I suggest using the Debug Book mod in that case to grant yourself inspiration points whenever appropriate.

Issues:

• The aforementioned blank background field thing. I don't know how to fix it, though honestly it's not that big of a deal. But if someone can fix it please go ahead.
• Inspiration: your companions will not be gaining any inspiration because I can't figure out how to add background goals. What I tried to do, instead of creating new goals, was to copy the existing goals from each character's corresponding generic background to their custom background, but I couldn't get it to work; way above my skill or knowledge. If someone who knows how to use NelsRelo's Inspiration Framework wants to take a stab at it, be my guest.
  

Installation:

• To install it using BG3MM just load it and the manager will place it in overrides automatically. 
• To install it manually put the pak file in your mods folder. 
• To install it using this Mac mod manager, install it but do not activate it.
  

Backgrounds:

Astarion: Trickster Hedonist (Deception, Stealth)
Lae'zel: Astral Zealot (Athletics, Intimidation)
Gale: Wizard of Waterdeep (Arcana, History)
Shadowheart: Cloistered Stray (Religion, Survival)
Wyll: Blade of Frontiers (Athletics, Persuasion)
Karlach: Blood War Veteran (Athletics, Survival)
Minthara: Underdark Exile (Deception, Intimidation)
Halsin: Grove Tender (Animal Handling, Nature)
Jaheira: World-Wise Heroine (Insight, Intimidation)
Minsc: Legend of Baldur's Gate (Animal Handling, Perception)

Thanks to lostsoulman, kilay, and NellsRelo  for helping me figure out how to make this on the Larian discord server.