Where were the Kena'ani?
Malbim: They were on the east and the west of the north side of the land.
What is the meaning of "ha'Chivi Tachas Chermon"?
Radak: It is the Chivi who dwelled under Chermon (in the valley
What is "b'Eretz ha'Mitzpah"?
Radak #1: This Chermon was in Eretz ha'Mitzpah.
Radak #2: All the kings gathered there to fight Yisrael. This was a greater salvation than overcoming the five kings. It is possible that Yehoshua built a Mizbe'ach due to the great salvation there, and Yisrael used to gather there when they needed to fight or for a great matter. We find Yiftach "Lifnei Hashem ha'Mitzpah" (Shoftim 11:11), and they gathered there at Pilegesh b'Giv'ah (Shoftim 20:1), Shmuel gathered Yisrael there in the war against Pelishtim, and when he rebuked the people for requesting a king (Shmuel 1 7:5, 1:10:17).