A transhumanism setting, competing upper castes of humanity have used magic to transform themselves into something more then human. Some of these castes fragments over philosophical differences hence subraces.
Humans are the lowest castes, they can't afford the cost of using magic to make themselves something more then human, or they object to the process in some cases based on philosophical and religious difference.
Halflings are the next caste up, they used magic to bend their luck, but something went wrong and they ended up weiry short. Officially they are a caste of spies, unofficially they are a caste of thieves.
The come the Gnomes, a merchant caste they actually made themselves short on purpose to make themselves look less dangerous. The Rock Gnomes deal craftsmen and the Forest Gnomes deal with Lumberjacks and farmers.
Next up are Orcs a Caste of Warriors, who are more merit based then most Castes, which is why Half Orcs are not only tolerated if they hold their own, but respected.
After that is the Tiefling Caste, who are guardians against horrors of the lower planes, they transformed themselves into a form more resistant to the fiendish energies of the lower planes at the cost of physically resembling the fiends they protect the world against. Almost universally respected as a force for good, even by ordinary humans.
The next higher caste are the Dwarves a physician caste that transformed themselves into a race that was more durable against disease and dangers.
Goliaths are the next caste up, enchanted professional athletes, Goliaths are usually very fameous.
Next up are the Elves are the nobles families who gift themselves with a longer life span and great beauty. They use magic on the lower caste humans to create half elves who act as intermediaries to lower impure castes, to minimize their exposure to those castes they feel are beneath them.
Genasi are the lower Priest caste who deal with the worship of Primordials. They used divine magic for their transformation, unlike lower castes that used arcane magic for their evolution. They also act as ambassadors with the Genie races.
Aasimar are the higher Priest caste, devoted to the Ester, the holy Gods and celestials.. In ancient times they were highly respected for their piety and that they used the strongest divine magics to evolves themselves closer towards the Gods. But over time their status has corrupted them and they are known to abuse their high status and precieved sancity.
Dragonborn are the Royal Families, each named after the race of Dragons that fused with their ancestors. When a Dragonborn dies having fulfilled their destiny, they are reborn as a true dragon. The Dragonborn Royal Families are the De Golds, the Dar Silvers, the Zarn Brass, the Mal Bronze, the Cas Coppers, the Drax Reds, the Bile Blues, the Nar Blacks, the Asna Greens, and the Chill Whites. Each rules over a nation.