Core definition that includes the five post-Soviet states in dark green.OverviewCentral Asia is a region of consisting of,,,, and most of. The countries as a group are also colloquially referred to as the "-stans" as all have names endi. One of the first geographers to mention Central Asia as a distinct region of the world was. The borders of Central Asia are subject to multiple definitions. Historically, political geography. Central Asia is a region of varied geography, including high passes and (), vast (, ), and especially treeless, grassy. The vast steppe areas of Central Asi.