This list does not include the earliest kingdoms, which were merely city states, except those that profoundly affected history.
a. Andreas Schachner 2011, Hattuscha: the oldest settlement is of 6000 BC; between 3200-2500 there is no habitation.
Hattum is the Akkadian name for Hattus(sa), the Hattian name is probably Ha-at-ti, so the same as the name of the land.
(Oǧuz Soysal 2004, Hattischer Wortschatz in hethithiser Text Überlieferung).
The Hattians lived in several kingdoms (city-states)in the Kizirl bassin of the Bronze Age.