From BiblePortal Wikipedia

Smith's Bible Dictionary [1]

Chu'shan-rishatha'im. (chief of two governments). The king of Mesopotamia, who oppressed Israel, during eight years in the generation, immediately following Joshua.  Judges 3:8. (B.C. after 1420). His yoke was broken from the neck of the people of Israel by Othniel, Caleb's nephew.  Judges 3:10.

Morrish Bible Dictionary [2]

King of Mesopotamia, who oppressed Israel for eight years: he was conquered by Othniel, Caleb's nephew.  Judges 3:8-10 .