Corinnguard
Hero
Backgrounds don't really say anything about culture specifically. They do, however, lend themselves to your character's origin as they represent who the character was before they left to become an adventurer. They also can be found in every culture in a given setting. And unless it's otherwise noted in the setting, a scribe in Waterdeep is going to be the same as a scribe in Neverwinter.What, in any way whatsoever, does this say about your culture?
The 3e Forgotten Realms Campaign Setting tried to introduce culture by making them regional. There was a table (pages 28-32) in the FRCS that broke the continent of Faerun down into regions. Each region gave a character a language they automatically knew and a list of bonus languages they could learn. They offered up regional feats and regional equipment too (magical and mundane).I will admit 5.24 isn't the best system, but I understand why WotC opted for keeping culture having limited mechanical impact to prevent having to create unique culture traits for every region, subrace, or lineage.
For instance, if your character hailed from the Dalelands, they would automatically know how to speak Chondathan and could learn Elven, Damaran, Giant, Gnome, Orc or Sylvan as bonus languages. They could also pick up the Blooded, Forester, Luck of Heroes, Militia or Strong Soul as a regional feat. In terms of equipment, someone from the Dalelands could get a Mighty Composite Longbow (+2), a Mighty Composite Shortbow (+2), a weapon (Longbow, shortspear or a quarterstaff), or a Potion of Cure Moderate Wounds.
I can imagine Level Up taking the Dalelands region and turning it into a Dalelands culture. Someone from the Dalelands would be proficient in the Longbow, Shortspear and Quarterstaff, regardless of their class. They would know how to read, write and sign in the human dialect of Chondathan as well as one or two of the above bonus languages. And they would be proficient in at least two skills.
The Forgotten Realms in 3e also had several books covering each region of Faerun.