Sheba and Dedan
The second son of Keturah by Abraham, Jokshan, had two sons Sheba and Dedan. Dedan is recorded as being the progenitor of the Asshurim, the Letushim and the Leummim (Gen. 25:3).
Confusion can arise with several of these names. For instance: although the term Asshurim here is related to Asshur (SHD 804), it refers to a different people from the Assyrians (also 804), who were descendants of Asshur son of Shem. Similarly, Sheba was the name given generations earlier to one of thirteen sons of Joktan, son of Eber (from whom the Hebrews are named).
Asshurim (SHD 805) means steps in the sense of taking steps to go somewhere. In later Jewish literature the Asshurim are described as ‘travelling merchants’.
Letushim (SHD 3912) means hammered or oppressed (Strong), directly related to a word (3913) meaning to sharpen, hammer, whet (BDB), that is, the Letushim were occupied in the sharpening of cutlery and weaponry.
Leummim (SHD 3817) means peoples or communities, from a root word meaning to gather. In later Jewish writings the Leummim are described as the ‘chief of those who inhabit the isles’, perhaps alluding to the Greek islands.

    This would also help to further explain the two major Semitic Haplogroups 
    of the Greeks
    being J and I with the later major haplogroup being the Hamitic E3b from North 
    African occupation there. These sons of Keturah may be the Laconian Greeks or
    Spartans although they did not inhabit the islands rather the mainland.
    Thus two branches of the sons of Keturah may be involved in Greece.

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