Halflings

The diminutive halflings survive in a world full of larger creatures by avoiding notice or, barring that, avoiding offense. Standing about 3 feet tall, they appear relatively harmless and so have managed to survive for centuries in the shadow of empires and on the edges of wars and political strife. They are inclined to be stout, weighing between 40 and 45 pounds.
The Halfling info can be found in the DND 5e Source books.