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Watson's Biblical & Theological Dictionary [1]

The Hebrew speaks of a people called Rosh,  Ezekiel 38:2-3 . "The orientals hold," says D'Herbelot, "that Japheth had a son called Rous, not mentioned by Moses, who peopled Russia, that is, Muscovy." We question not but Rosh, or Ros, signifies Russia, or the people that dwell on the Araxes, called Rosch by the inhabitants; which was the habitation of the Scythians. It deserves notice, that the LXX render the passage in Ezekiel, Γωγ , αοχοντα ‘Ρως , Μεσοχ , και Θοβελ , Gog the chief of Ros, Mesoch, and Thobel; and Jerom, not absolutely to reject this name, inserts both renderings: Gog, terram Magog, principem capitis ( sive Ros) Mosoch, et Thubal. Symmachus and Theodotion also perceived Ros to be in this place the name of a people; and this is now the prevailing judgment of interpreters. Bochart, about A.D. 1640, contended that Russia was the nation meant by the term Ros; and this opinion is supported by the testimony of various Greek writers, who describe "the Ros as a Scythian nation, bordering on the northern Taurus. Mosok, or Mesech, appears to be the same as the Moskwa. or Moscow, of the moderns; and we know, that not only is this the name of the city, but also of the river on which it stands. See Gog .

Fausset's Bible Dictionary [2]

"Chief" ( Ezekiel 38:2-3;  Ezekiel 39:1). Rather, as not Rosh but Nasi is the head of a nomadic tribe ( Genesis 23:6), "Magog, the prince of Rosh, Meshech, and Tubal," three great Scythian tribes of which gosh is the first. Rosh is the tribe N. of the Taurus range and near Rha or Volga which gives them their name; the earliest trace of the Russ nation. A Latin chronicle A.D. 839 (Bayer, Origines Russ., 1726, p. 409) is the first modern mention of this now mighty people. Tiras stands for Rosh with Meshech and Tubal ( Genesis 10:2). Others state that the modern Russians have assumed their name from Rhos, the Araxes, though their proper ancient name was Slavi or Wends. Hengstenberg supports KJV: "Magog was Gog's original kingdom, though he acquired also Meshech and Tubal, so as to be called their 'chief prince.'"

Hastings' Dictionary of the Bible [3]

ROSH . 1 . A descendant of BenjaminGenesis 46:21 [text doubtful]). 2 . In   Ezekiel 38:2 f.,   Ezekiel 39:1 the word Rosh is thought by many interpreters to refer to a people, otherwise unknown, but coupled with Meshech and Tubal (wh. see). It is possible, however, that the word meaning ‘bead’ is used as a preposition ‘over,’ so that the phrase here applied to Gog (wh. see) simply means, ‘prince over Meshech and Tubal’; cf. AVm [Note: Authorized Version margin.] .

J. F. McCurdy.

Morrish Bible Dictionary [4]

1. Son of Benjamin.  Genesis 46:21 .

2. The same Hebrew word occurs in   Ezekiel 38:2 and   Ezekiel 39:1 , which, though frequently translated 'chief,' is now treated in these passages as a proper name reading 'prince of Rosh,' as in the R.V. and other translations. It refers to Russia.

Smith's Bible Dictionary [5]

Rosh. (Head).

1. In the genealogy of  Genesis 46:21, Rosh is reckoned among the sons of Benjamin.

2.  Ezekiel 38:2-1;  Ezekiel 39:1. Probably, a proper name, referring to the first of the three great Scythian tribes, of which Magog was the head.

Hawker's Poor Man's Concordance And Dictionary [6]

One of the sons of Benjamin, ( Genesis 46:21) Rosh means head. Probably, therefore, this son of Benjamin became the head of a family.

Holman Bible Dictionary [7]

 Genesis 46:21 Numbers 26:38-39 1 Chronicles 8:1-5

Easton's Bible Dictionary [8]

 Ezekiel 38:2,3 39:1Bethshean

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [9]

(Heb. Rosh, ראֹשׁ , Head , as often; Sept. ῾Ρώς ), the name of a man and perhaps of a people. (See Gall).

1. The seventh named of ten sons of Benjamin, each of whom was head of a family in Israel ( Genesis 46:21). B.C. cir. 1880. He is perhaps identical with the Rapha of  1 Chronicles 8:2. (See Jacob). "Kalisch has some long and rather perplexed observations on the discrepancies in the lists in Genesis 46 and Numbers 26, and specially as regards the sons of Benjamin. But the truth is that the two lists agree very well so far as Benjamin is concerned; for the only discrepancy that remains, when the absence of Becher and Gera from the list in Numbers is explained [see those words], is that, for the two names אהי and ראש (Ehi and Rosh) in Genesis, we have the one name אחיר ם (Ahiram) in Numbers If this last were written רא ם , as it might be, the two texts would be almost identical, especially if written in the Samaritan character, in which the Shin closely resembles the Memo That Ahiram is right we are quite sure, from the family of the Ahiramites, and from the non mention elsewhere of Rosh, which, in fact, is not a proper name. The conclusion, therefore, seems certain that אחיוראש in Genesis is a mere clerical error, and that there is perfect agreement between the two lists. This view is strengthened by the further fact that in the word which follows Rosh, viz. Muppim, the initial M is an error for Sh. It should be Shuppim, as in  Numbers 26:39;  1 Chronicles 7:12. The final m of Ahiram and the initial sh of Shuppim have thus been transposed."

2. The Heb. word Rosh , rendered "prince" ( Ezekiel 38:2-3;  Ezekiel 39:1), ought to be read as a proper name, as in the Sept. "the chief" or "prince of Rosh, Meshech, and Tubal." Rosh thus appears as the name of a northern nation, along with Meshech and Tubal (comp. Rhoas, in Pliny, 6, 4, which may be a city, a river, or a people, between Suavi and the district Erectoe, on Caucasus; and Rhadsh, an Iberian province in the same place, named by Russegger [Beschreib. d. Caucas. 2, 34]). Gesenius says, "Without much doubt Rosh designates the Russians, who are described by the Byzantine writers of the 10th century, under the name of the Roos, as inhabiting the northern parts of Taurus; and also by Ibn-Fosslan, an Arabic writer of the same period, under the name Rus, as dwelling upon the river Volga" (Thes. Heb. s.v.). The Oriental writers say that Rus was the eighth son of Japhet, and his descendants are, by Abulfaraj, always joined with the Bulgarians, Slavonians, and Alani. For other suppositions, see Stritter, Memor. Populorolin ad Danub., etc., Habitant. 2, 957 sq.; Michaelis, Suppl. 6, 22-24 sq.; Bochart, Phpal. 13, 13; Schulthess, Parad. p. 193; Ierbelot, Biblioth. Or. 3, 137 sq. If the view of Gesenius be correct, in this name and tribe we have the first trace of the Russ, or Russian, nation. "Von Hammer identifies this name with Rass in the Koran (25, 40; 1, 12), the peoples Aad, Thamud, and the Asshabir (or inhabitants) of Rass or Ross.' He considers that Mohammed had actually the passage of Ezekiel in view, and that Asshabir' corresponds to Nasi, the prince' of the A.V., and Ἄρχοντα of the Sept. ( Surm Les Origines Russes [St. Petersb. 1825], p. 24-29). The first certain mention of the Russians under this name is in a Latin Chronicle under the year A.D. 839, quoted by Bayer ( Origines Russicoe , Comment. Acad. Petropol. [1726], p. 409). From the junction of Tiras with Meshech and Tubal in  Genesis 10:2, Von Hammer conjectures the identity of Tiras and Rosh (p. 26). The name probably occurs again under the altered form of Rasses (q.v.) in  Judith 2:23 this time in the ancient Latin, and possibly also in the Syriac version, in connection with Thiras or Thars; but the passage is too corrupt to admit of any certain deduction from it. This early Biblical notice of so great an empire is doubly interesting from its being a solitary instance. No other name of any modern nation occurs in the Scriptures, and the obliteration of it by the A.V. is one of the many remarkable variations of our version from the meaning of the sacred text of the Old Test."