Since the name Amorite can be used to refer to all the inhabitants of the land (Genesis 15:16), it might be best to understand these two kings as referring to the ringleaders of the northern and southern coalitions. Thus Adoni-zedek and Jabin (Joshua 10:3; Joshua 11:1–3).1
12 And I sent the hornet before you, which drove them out before you, the two kings of the Amorites; it was not by your sword or by your bow.