In Ardashir's period, though the centralization had begun and the number of local shahs had decreased sharply, his reign stood on the same bases which the Parthian empire was on after all. According to the description of Shapur I's inscription at the Ka'ba-ye Zartosht of Ardashir's court, the latter's name is mentioned as the king of kings (shahanshah) along with four "shahs", who were the rulers of Nishapur, Marw, Kerman and Sakastan. There were also the three kingdoms Makran, Turgistan and Kushanshahr that had submitted to Ardashir's command and paid him taxes. Those local shahs were partly semi-dependent from the central government and the successions were inherited for them. However at the periods of the succeeding Sasanian shahanshahs, the independences of some of them were taken; for example at the time of Shapur I, the independences of Merv and Nishapur were taken and Sakastan became a province (city) and was granted to liegeman Narseh, son of Shapur. This shows an increasing inclination towards the centralization of power since the early Sasanian era. The structure of the central Parthian government depended on "local noblemen" and "clan grandees" and included local autonomous governments based on "aristocracy" and "tribal interests". Ardashir had realized that it would be impossible to pursue and finish the policy of attacking and attaching without permanentizing and consolidating power in his domain; and thus, he could alter the military balance in then status and the homeland structure only by removing the local governors and establishing a central power with an organized bureaucratic system. Although the Sasanian government did not have any difference from the final Parthian era on its first days, but as mentioned, one of the prominent features of the Sasanian era was an increasing inclination toward the concentration of power in Iran since the first days of the Sasanians' uprising. In the Sasanian dawn, Iran included a union of kingdoms and noble landlords (liegemen), each of which possessed a various degree of independence from the central government and were economically connected to it by different channels. In other words, a type of feudal society under the rule of large owners stood in the Iranian Plateau while in the Mesopotamian deserts, the urban culture and pathway cities were the face of society more often. Urbanization The first Sasanian shahanshahs founded or renovated some cities in different Iranian regions. It is clear from the first Sasanian inscriptions that "altering