Alexander the Great (365-323BC) recorded that his soldiers were afraid of the dragons when they invaded India. Marco Polo (1254-1324) was an explorer who went to China among other places. On coming home he reported that the emperor of China was raising dragons to pull his chariots.
These historical records, along with many others, mean that dinosaurs (called dragons before 1841, when the word dinosaur was invented) were alive as late as 1324 AD. Today many scientists tell us they all died off millions of years ago. Many human sightings provide far more evidence than the theory (no evidence) of these scientists.
Here is a fictional example from Lord of the Rings, where mammoth’s are trained as weapons for war.