In the Ancient World fossils were often used as evidence a of place previously being underwater. What we would call dinosaurs, they called monsters. You maybe interested in the Nichoria bone. It's a Mammoth bone, discovered first by the Ancient Greeks. According to the linked article:

the ancient Greeks found the bone in the lignite deposits of the Megalopolis basin, known in antiquity as the 'Battleground of the Giants.' There, the dense concentration of large fossil bones inspired the belief that entire armies of giants were blasted by Zeus's thunderbolts

In China dinosaur bones inspired the "dragon" myth. Chang Qu mentions in the 4th C BC that dragon bones were found in what is now Sichuan Province.