In a historical sense, statelessness could reasonably be considered to the default human condition that existed universally from the evolution of human species to the emergence of the first human civilizations. Historically in every inhabited region on Earth, prior the emergence of states as polities humans organized into tribal groups. In the absence of written laws, people living in tribal settings were typically expected to adhere to tribal customs and owed allegiance to their tribe and/or tribal leaders. As states began to form, a distinction developed between those who had some form of legal attachment to a more complex polity recognized to be a state in contrast to those who did not. The latter, often living in tribes and in regions not yet organized into and/or conquered by more powerful states, would widely be considered to be stateless in a modern sense. Historically, there is considerable correlation between those who would meet the modern definition of statelessness and those the contemporary ruling classes of the extant states would have deemed to be mere barbarians.