An Excerpt from De Martino’s Paper
It appears that more scholars are adopting the idea that the name of the Mitanni kingdom (whose archaic form was Maitani) was derived from the name of a person or clan that founded the kingdom. De Martino does not mention it, but there is evidence from the Upper Euphrates that may support this interpretation. A certain Mita from Pahhuwa (near Hayasa), who lived in the 15th century BCE, is known to have rebelled against the Hittites.
This indicates that the name Mita indeed existed during that period. However, we should not rush to the conclusion that the founders of Mitanni came from the Upper Euphrates. The Mita from Pahhuwa may well have had an Indo-Iranian origin and could have moved there from the south. Fournet has proposed an Aryan etymology for this name.
At the same time, other scholars express skepticism that the first legendary ruler, Mita/Maita — who is not directly attested in the sources — had an Indo-Iranian name. The same applies to the second ruler, Kirta, who is mentioned only once. Starting with his son, however, all the kings bear Aryan names.
Additionally, the Greek-period term Matiene may represent a legacy of the Mitanni. Apparently, in antiquity there were still groups who identified themselves with the Mitanni polity that collapsed around 1200 BCE. What languages these groups spoke is difficult to determine.