Although the economics and politics have mutual influences, they do not go necessarily hand in hand. From the conquest by Arabs to Mongol invasion, because of its place in Khorasan road and suitable conditions for agriculture, Merv was a good instance of economic stability and growth, in spite of its political evolutions and changes. With the rise of Islam, Khorasan road as a well-known and main road between China and Baghdad-the Abbasid capital-and of course Merv in this road had an important role in the trade between east and west. In every year many caravans went to China to bring a lot of goods such as silk, musk, camphor and cinnamon. Merv as one of the most important city in Khorasan road, was ruled by many dynasties, however, enjoyed a relative stability most of the time. The Mongol invasion caused a serious changes in both its political and population context.