Backgrounds & Skill Checks
Backgrounds represent pieces of your character’s history that contributes to your character’s history as well as their ability to succeed with non-combat skills.
This is a variant rule from the DMG that replaces skills and tools proficiencies with character backgrounds. These are broad categories of experience (cat burglar, for example) rather than specific implementations of that experience (climbing and hiding).
Backgrounds don’t sync to a specific ability score, though some backgrounds obviously may get used more often with certain ability scores than others.
Anything the would grant the character a skill or tool proficiency provides no benefit. Instead, a character can add his or her proficiency bonus to any ability check to which the character’s prior training and experience (reflected in the character’s background) reasonably applies.
For example, the player of a character with the noble background could reasonably argue that the proficiency bonus should apply to a Charisma check the character makes to secure an audience with the king.
If the character has the Expertise feature, instead of choosing skills or tools to gain the benefit of that feature, the player defines aspects of his or her background to which the benefit applies. Continuing with the noble example, the player might decide to apply Expertise to “situations where courtly manners and etiquette are paramount” and “figuring out the secret plots that court members hatch against one another.”
Alternately, the player can apply the proficiency bonus to any ability check directly related to the character’s positive personaility traits. For example, a character with the positive personality trait of “I never have a plan, but I’m great at making things up as I go along” might apply the bonus when engaging in some off-the-cuff deception to get out of a tight spot.
However, when a character’s negative personality trait directly impacts an ability check, the character has disadvantage on the check.
When a character gains a new skill or tool they can add a new personality trait or a new background.
What is a Background?
A background in this instance is at least a word but better yet a phrase that says something about your past. For example, some one-ish word examples: thievery, acrobat, alchemist, animal trainer, architect, aristocratic noble, assassin, Cathedral servitor, chef, conwoman, dinosaur hunter, goblin exterminator, hunted outlaw, knight errant, Legionnaire of the 17th Legion, magecraft, priest, refugee, scout, shepherd, soldier, spy, temple acolyte, thief, torturer, transformed animal, traveling martial arts pupil, tribal healer, tunnel scout, wandering minstrel, warrior poet, and so on.
Those are all fine, but a better example is a phrase, for example instead of thievery you put “member of the thieves guild of Berlin” now you can make a case for contacts in the guild, fences, perhaps a language or two, some area knowledge, guild practices, etc; and if you are feeling dangerous you might try, “head of the thieves guild in Berlin, the Silent Purses” now you have what you had before and can make a case for some leadership skills.
And just as you might have a couple of skills on your sheet you might have a couple of backgrounds (probably not a one to one correlation), before becoming the head of the thieves guild, you might have served as “a cabin boy aboard the Bretonian pirate ship, ‘Johnny’s Marrow’ raiding in the Sea of Elves”.
I’d suggest a primary background with a couple of secondary backgrounds as being a good place to start. If you get creatively inspired by your muse, stop at four backgrounds or somehow combined them into four backgrounds to start with.