What do we learn from "ha'Ro'eh Chatzi ha'Menuchos"?
'Rashi', Radak #1: There was one Medinah in the land called Menuchos - "va'Yaglum El Manachas" (8:6). Shoval ruled over half of it 1 ; below it says who ruled over the other half.
Radak #2: He ruled over half of Yerushalayim, which is called Menuchah.
Radak #3: He was appointed over half the Menachos that came to Yerushalayim from all the Goyim 2 .
Radak himself: These are the names of two sons of Shoval - ha'Ro'eh, and Chatzi ha'Menuchos. Do not be astounded that these are names - also "Gidalti v'Romamti" (25:4) are names.
Malbim: Ha'Ro'eh is Re'ayah ben Shoval (4:2). "Avi" applies to Chatzi ha'Menuchos - he ruled over half the city. Alternatively, half the residents descended from him, and pertained to his Beis Av.
Malbim: Some say that these are the names of three sons - ha'Ro'eh, Chatzi and ha'Menuchos. Do not be astounded at the initial Hei. Many names begin with Patach [or Kamatz] Hei, e.g. "ha'Tzlelponi", "ha'Achashteri", "ha'Tzovevah", "ha'Rum" (4:3, 6, 8), "ha'Soferes", "ha'Kotz" (Ezra 2:55, 41) and many others.
