Analysis of the factors of failure of Amir Massoud Sarbadari in the expedition to Mazandaran based on Theories of war by Sun Tzu

Amir Massoud, as one of the influential rulers of Sarbadari, was able to expand the  Sarbedaran’s territory beyond the Beyhaq area after gaining power, but in the last year of his rule,  he lost his life and many of his military forces with a heavy failure in the campaign to Mazandaran, and in this way, Sarbadaran suffered an irreparable stroke..Considering the importance of the battle of Mazandaran, this article tries to analyze the factors of Amir Massoud's failure in this campaign based on historical sources close to the event, related researches and the treatise on the art of war, and using the descriptive-analytical method and the application of Sun Tzu's martial views.. The findings show that Amir Masoud’s failure is related to both sides of the battle’s behavior; Amir Masoud, regardless of the heterogeneous situation of his troops after the defeat of Zawah, engaged them in an erosion battle and without any useful tactics, he openly went into depth of Mazandaran. The rulers and people considered him as a common enemy and united against him and they caused him and his forces to be surprised and destroyed with an efficient strategy. .