A Back-Foot from the Nurenburg Chronicle, 1493

THE NULOI (or Nuli) were a tribe of Indian men with backward-facing, eight-toed feet.

Pliny the Elder, Natural History 7. 23 (trans. Rackham) (Roman encyclopedia C1st A.D.) :
"Megasthenes [Greek historian C4th B.C.] states that on the [Indian] mountain named Nulus there are people with their feet turned backwards and with eight toes on each foot."

Sources:

• Pliny the Elder, Natural History - Latin Encyclopedia C1st A.D.