The Yellow River has long been known as the cradel of ancient Chinese civilization. One of the first to spring forth in this area is sometimes called the Huang He, Longshan Culture or Yellow River Civilization. It began between 4000 and 3000 BCE and was ruled by a king who commanded the loyalty of several regional warlords. The civilization is best known for the distinctive black pottery it produced, which is found in many burial sites along the river.
Around 2000 BCE there was a sharp decrease in population. The black pottery began appearing less frequently which had led most historian to believe that some sort of environmental distaster damaged crucial crops. It is possible that an increase in rainfall for a long amount of time caused erosion which led to mass starvation and the eventualy break-up of the centralized government power. It is difficult to say for certain since much of China's ancient history is coupled with myth and legend.