>>42727383 (OP)
Pinkie Pie: Clearly Amish. 100% pure Aryan phenotype.
Rarity: Puts on the Trans-Atlantic accent to try and fit in with the upper crust. Her talent eclipses the truth she’s nouveau riche. Still has strong Norwegian or Swedish heritage.
Applejack: Scotch-Irish stock. Regardless of whether an Appalachian-American is landed or impoverished, they’re prone to violence and grudges, but will wade through Hell and high water if they consider you a friend.
Rainbow Dash: The All-American girl from the Midwest but got accepted into private school due to athletic merit. Has strong English-Welsh blood due to her tomboyish nature.
Fluttershy: Tremendous amount of French ancestry due to her multifaceted talents in art and culture, while also retaining a model-like body and facial structure.
Twilight: Ashkenazi Jewish. A daughter of wealth, privilege, and prestige, fiercely intelligent but also prone to numerous neuroses.