That's a part of history that needs to be investigated: just what, if anything, the Muslims invented and what did the take from conquered cultures and claim as their own? I think several of their "inventions" really came from the Hindus.
Check Dan Pipes’ site - he wrote a piece long time back with some of this - the muslim claim to Jerusalem. There is no need to investigate, history is history.
What’s been going on for a while is the re-writing of it by muslims much like the soviets did in the 40s, claiming invention of, discovery of just about everything.
What muslims are saying is: these are the items outside of the koran, which we will accept as legitimate, everything else we will destroy.