This is part of the Red Box Fate series.
Turning D&D's "races" (ugh, no - we're going to call that "Kin"), and 5th Edition's backgrounds and bonds into Fate-style Aspects is pretty simple. Yes, I know Old School didn't bother with Backgrounds, Flaws and Bonds, but they're quite helpful for the Fate style play, so we're stealing them.
These mostly take the place of the High Concept and Trouble - there will be some overlap with your "class" but we're not going to worry about that here yet.
Backgrounds
Every story has a beginning. Your character’s background reveals where you came from, how you became an adventurer, and your place in the world. Your fighter might have been a courageous knight or a grizzled soldier. Your wizard could have been a sage or an artisan. Your rogue might have gotten by as a guild thief or commanded audiences as a jester.
Your background should provide both concrete benefits (features, proficiencies, languages, etc) and roleplaying opportunities.
We'll use these narratively, not as fixed bonuses or once-per-day tricks, but to explain why your character has certain skills, or how the world perceives them.
With your background, you'll have a narrative reason to say "Because I was a hunter, I carefully scan the path for tracks," or "I use my noble background to forcefully press the gatekeeper into letting us pass," or "I flashily sing a bawdy song to distract the crowd while my friends slip out the back," or "Of course everyone round here likes me because of that time I lead the charge against the Winter Raiders - we'll have no trouble getting food and lodging."
Work with the GM to create any background you want - but here are some examples from D&D. You can use these examples to guide you on adapting any of the published backgrounds.
Acolyte
You're a person of the cloth, a recognised and respected religion in the game setting. Those of your church will give you and your companions shelter. You have a deep insight into people's behaviour from the lessons of your scripture. Aside from your almost perfect knowledge of your own faith, you know many things about the religions of others, including those who oppose your faith. You know more languages than usual.
Noble
You're member of the nobility, your family owns or rules lands, you have a title. People are inclined to think the best of your, that you belong in high society, and commoners try to accommodate you and avoid your displeasure. You know the history of the houses of the nobility. You are at home in courtly social situations. You've learned an extra language.
Outlander
You've lived outside of civilisation as a wanderer. You have a knack for navigation - once you've visited a place or read a map, you are almost never lost - and you know how to forage for available food and water, tracking an hunting wild game. You are capable at scrambling over tough terrain. You have picked up the language of a nearby culture.
Sage
You have studied lore and learning. You know your way around libraries and scriptures, and can dig through their secrets better than most. You have an understanding of history and arcane matters, and can apply this knowledge in dynamic ways. You know more languages than usual. You've made one particular topic the focus of your learning.
Kin
Kin is a special aspect that adds to your Background. Your biological and cultural heritage will be a big part of who you are. Instead of keying this as a bunch of granular bonuses and penalties, and special abilities, in Fate terms, we're going to just write "Elf" "Human" "Dwarf" or whatever as part of your High Concept Aspect.
Maybe not just write that - in D&D, each Kin sets some of your descriptions, so we'll need to retain Ability Score Increase, Size, and Speed. The rest can be wrapped up in describing the Kin aspect.
You and the GM will work out what all that means in your game - but here's how those things work for a selection of the common D&D kin, to give the most seamless D&D conversion.
Dwarf
Ability Score Increase: Your Constitution score increases by 2.
Size: Dwarves stand between 4 and 5 feet tall and average about 150 pounds. Your size is Medium.
Speed: Your base walking speed is 25 feet. Your speed is not reduced by wearing heavy armour.
Because of their life underground, Dwarves can see well in the dark. They are competent with the tools and weapons of their culture - hammers and axes, smithing and masonry. They know the history of stone, whether worked or natural. Dwarves speak Common and Dwarvish.
Elf
Ability Score Increase: Your Dexterity score increases by 2.
Size: Elves range from under 5 to over 6 feet tall and have slender builds. Your size is Medium.
Speed: Your base walking speed is 30 feet.
Elves have keen senses, they can see far off, and in moonlight and starlight almost as well as broad daylight. Their connection to the Fey folk means they easily slip out of or avoid enchantment magic.
Elves speak Common and Elvish.
Halfling
Ability Score Increase: Your Dexterity score increases by 2.
Size: Halflings average about 3 feet tall and weigh about 40 pounds. Your size is Small.
Speed: Your base walking speed is 25 feet.
Despite their small size, Halflings make great adventurers because they are supernaturally lucky, inherently brave, and nimble.
Halflings speak Common and their own language.
Human
Ability Score Increase: All your ability scores each increase by 1.
Size: Humans vary widely in height and build, from barely 5 feet to well over 6 feet tall. Regardless of your position in that range, your size is Medium.
Speed: Your base walking speed is 30 feet.
Generally Humans get along well with the other Kin - it's said that they are everyone's second favourite.
Humans speak Common, and may learn any other language, especially those of their neighbours.
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Remember, the Fate way of thinking means you can refer to your Background (including Kin) to explain why your character is able to anything appropriate for your character in the narrative, without having to spend any special effort.
You can also use your Background and Kin with a Fate Point to gain special advantages and abilities when it's dramatic and cool.
Bonds & Troubles
D&D 5th edition introduced us to Flaws and Bonds and Inspiration - roleplaying hooks we can use to gain gain rewards in the metagame. Players of Fate and other systems shrugged and said "Nice of you to join us, finally."
Sarcasm aside, these should be very familiar ideas from both sides of the fence - both work to get you in-game bonuses. I'll be using the Fate concept of your character's Trouble to replace the Bonds of D&D.
When you play up to your Trouble, you can claim a Fate point from the GM. Also, the GM can point out that your Trouble should drive your character's behaviour (the GM should never use this to steer you in a particular way, but to nudge you into drama).
Trouble - paraphrased from Fate Core
If your high concept is what or who your character is, your trouble is the answer to a simple question: what complicates your character’s existence?
Trouble brings chaos into a character’s life and drives them into interesting situations.
Your trouble shouldn’t be easy to solve. If it was, your character would have done that already, and that’s not interesting. But nor should it paralyze the character completely. If the trouble is constantly interfering with the character’s day-to-day life, he’s going to spend all his time dealing with it rather than other matters at hand. You shouldn’t have to deal with your trouble at every turn—unless that’s the core of one particular adventure in the story (and even then, that’s just one adventure).
Troubles also shouldn’t be directly related to your high concept — if you are a Stalwart Paladin of Chronos, saying your trouble is The Heretics Hates Me is a dull trouble, because it is already assumed with your high concept. (Of course, you can turn that up a notch to make it personal, like Elder Zarquon Personally Hates Me, to make it work.)
Before you go any further, talk with the GM about your character’s trouble. Make sure you’re both on the same page in terms of what it means. Both of you may want to find one way this aspect might be invoked or compelled to make sure you’re both seeing the same things—or to give each other ideas. The GM should come away from this conversation knowing what you want out of your trouble.
Since your trouble is an aspect, it’s something you should also be able to invoke, right? Because you've been so focused on how this complicates your character’s life, it’s easy to miss how a trouble also helps your character.
In short, your experience with your trouble makes you a stronger person in that regard. Dealing with personal struggles leaves you vulnerable to being tempted or cajoled, but it can also give you a sense of inner strength, because you know the sort of person you want to be. Problematic relationships often cause trouble, but people do learn hard lessons from the troubles they deal with. They especially learn how to manoeuvre around many of the smaller issues their troubles present.
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Credits
I'm indebted to Killershrike's "Pathfinder Fate Accelerated" for the initial idea that this sort of thing could be done - without their groundwork, I'd have been lost.
Of course the Creative Commons access to D&D's engine and FAE are essential as well - D&D is CC-BY-4.0, FAE is CC-BY-3.0
Old School Essentials collects much of the D&D Basic and Expert set rules into one handy SRD, which you can find here.
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