Seleucus inherited a rather large chunk of land, extending from Anatolia in the west to the borders of India in the east. You could say he hit the "lottery" but at the same time he inherited much more than he bargained, more so for his future inheritors of this vast domain. One of the biggest problems in controlling such a vast amount of land is the issue of holding onto it. In other words, the land is too big to use for it is too big to lose. One has to consider, especially those in the Seleucid administration, that there are going to be language barriers, but even more important than language barriers, are the cultural barriers. Because of these cultural barriers, it was easier to allow the locals to govern. In this way, the Seleucids could control their eastern provinces more effectively. However, even this is a façade. While the Seleucids allowed the locals of their eastern provinces to govern, it also created a friction between the two cultures. In other words and as you shall read, the Seleucids began to ignore their supposed subjects of the east. Ignoring the various peoples on the Iranian Plateau and areas further to the east under Seleucid control caused many of them, including Greco-Macedonians, to question the intent of their masters further west. In doing so, many would secede in the east. This secession from the Seleucids enticed certain nomadic tribes, such as the Aparni (Parthians), to invade, conquer, confiscate and colonize the weakest breakaway provinces. The Seleucid regime's uncertainty allowed a small tribe from the north to invade a breakaway province considered Seleucid territory that, in turn, would go on to nearly re-conquer everything Alexander the Great had subdued almost a century earlier.