Synthesis occurs when you take a number of disparate pieces of information and construct a story of your choosing from that. Please note that in wikipedia we report stories that are constructed by respectable scholars and are reported in reliable sources. If it takes you 1500 words to make the case that the general area near the pass was once said by someone to be in Kashmir and therefore it is in Kashmir, you really should submit this to a peer reviewed journal. Wikipedia will gladly then include the material in the article, properly referencing your paper. In the meantime, you are in danger of being blocked from editing wikipedia, which I will do if a few more editors present evidence of tendentious editing on other articles.  (My narrowboat)