Construction of Engaruka has traditionally been credited to the ancestors of the Iraqw, a Cushitic-speaking group of cultivators residing in the Mbulu Highlands of northern Tanzania. The modern Iraqw practice an intensive form of self-contained agriculture that bears a remarkable similarity to the ruins of stone-walled canals, dams and furrows that are found at Engaruka. Iraqw historical traditions likewise relate that their last significant migration to their present area of inhabitation occurred about two or three centuries ago after conflicts with the Barbaig sub-group of the Datoga, herders who are known to have occupied the Crater Highlands above Engaruka prior to the arrival of the Maasai. This population movement is reportedly consistent with the date of the Engaruka site's desertion, which is estimated at somewhere between 1700 and 1750. It also roughly coincides with the start of the diminishment of the Engaruka River's flow as well as those of other streams descending from the Ngorongoro highlands; water sources around which Engaruka's irrigation practices were centered. According to the Maasai, who are the present-day occupants of Engaruka, the Iraqw also already inhabited the site when their own ancestors first entered the region during the 18th century.