Now the sons of Keturah, Abraham's concubine: she bare Zimran, and Jokshan, and Medan, and Midian, and Ishbak, and Shuah. And the sons of Jokshan; Sheba, and Dedan.
Sons of Keturah. Those became founders of nomadic tribes in the north of Arabia and Syria as Midian of the Midianites (Genesis 36:35; Judges 6:2).
And Shuah - from whom Bildad sprang (Job 2:11).