SO (Heb. סוֹא), according to the received text of II Kings 17:4 the name of the king of Egypt with whom King *Hoshea of Israel entered into relations in approximately 725 B.C.E. when he discontinued the annual payment of tribute to his Assyrian suzerain.
Whereas סוא-swʾ does not correspond to the name of any known Egyptian prince or general, it can very well be equated with Egyptian sw, cuneiform Sa-a-a, and Greek Sais, the name of the city in the western Delta which was the residence of the pharaoh Tefnakhte; and since it now appears that the latter was already reigning over Lower and Middle Egypt at this time, H. Goedicke has suggested that this is the Pharaoh in question. After Goedicke, W.F. Albright has proposed for the pertinent clause in II Kings 17:4 a reconstruction which yields the required sense. But it can be achieved more simply: the mere inversion of the words so and el, without any addition, makes the clause mean, "For he had sent a mission to Sais, to the king of Egypt" (cf. I Sam. 23:3b; II Sam. 3:20b; I Kings 2:26ab). R. Sayed has suggested that סוא-swʾ is shortened from Si-jb, which is now known to have been Tefnakhte's Horus-name; but he observes that the normal thing is for a foreign document to refer to Pharaoh by his name or (in the *el-Amarna correspondence) his praenomen (or merely by the title Pharaoh), not by his Horus name. Most recent scholarship (contrast Green) has accepted Goedicke's 1963 identification of "So" as a place name, and the identification of the Pharaoh ruling there as Tefnakhte.
S. Yeivin, in: VT, 2 (1952), 164–68; H. Goedicke, in: BASOR, 171 (1963), 64–66; W.F. Albright, ibid., 66; R. Sayed, in: VT, 20 (1970), 116–18. ADD. BIBLIOGRAPHY: M. Cogan and H. Tadmor, II Kings (AB; 1988), 196; B. Becking, The Fall of Samaria (1991), 47 n. 2; J. Day, in: VT, 42 (1992), 289–301; A. Green, in: JNES, 52 (1993), 99–108; P. Galpaz-Feller, in: RB, 107 (2000), 338–47.