Although they didn’t know what a dinosaur was, there are records of fossils being found thousands of years ago. Several ancient civilizations arose in areas that paleontologists now know to be fossil rich. The limestone that the Egyptian pyramids are made of is filled with fossilized sea creatures. Also, Greek historians recount tales of giant bones being found that they believed to be the skeletons of their legendary heroes and mythical monsters.

More can be written about this, but you might find pertinent a couple of articles in the FAQ section "Biology, evolution, and fossils":

"Is it possible that dinosaur fossils played some role in the origin of dragon myths?" by /u/Dashukta

"Is there any evidence of cultures finding dinosaur fossils before the 17th century? If so, what were their reactions or beliefs surrounding the fossils?" by [deleted]

This is not to discourage discussion. Further questions, data, and debate are welcome.