Over time, historians, scholars, archaeologists have broken the human history of Atvas into six distinct periods based on various sudden changes.
The Dotan (Saigar: Do "Before", Tan "Civilization") Period has no defined beginning and is the period of all time before the appearance of the first cities, around 7,000 H.D.
The Luudyrg Period, named for the ancient city of Luud, begins around 7,000 H.D. and is marked by the sudden and rapid appearance of a number of the first cities found on Atvas, along with the advent of agriculture, complex societies, writing, and organized religion.
This period begins with simple city-states with limited trade and contact with each other and eventually evolves into larger cultures and long distance trade routes.
Named for the two dominant cultures, the Nansha and Tantun, who reached their peak at the beginning of this period, it begins around 5,000 H.D.
This period is noted for the emergence of the very first kingdoms and empires on record, as well as rapid technological advancement.
The Zahandyrg Period's start is marked by the sudden collapse of the Nanshan and Tantun cultures and is named for the large Zahandu Empire that existed during this time, starting around 2,500 H.D.
This period is marked by a great "dark age" experienced by several cultures outside the Zahandu Empire as well as a number of very bloody wars.
Beginning around 1,000 H.D. this period is named for the culture that evolved from that of the Zahandu culture after the empire broke apart into a series of city states. Eventually the Tairese people were united under two opposing dynasties, the Safik and the Doan.
Gan Uyr's rise to power and conquest of over half of Atvas took place near the very end of this period.
The unification of all people of Atvas under Hadis-Khuvan Khula and the Saigar Khuvanate in 57 D.H.K. marks the beginning of the Khuvan period, which continues today.