Here they lived among the Amalekite Bedawin down to the days of Saul.

To the last they maintained their nomadic habits, and the Kenite family of Rechab still dwelt in tents and avoided wine in that later age when the kingdom of Judah was about to fall.[3] The Edomite element in Judah was stronger than the Kenite.

It consisted of the two clans of Jerahmeel and Kenaz, or the house of Caleb as it was called in the time of David.[4] Kenaz was a grandson of Esau, and the fact that the Kenizzites shared with the Israelitish tribes in the conquest of Canaan throws light on the law of Deuteronomy[5] which gave the Edomite of "the third generation" all the rights and privileges of a Jew.

Caleb, the conqueror of Hebron, was a Kenizzite; so also was Othniel, the first of the Judges of Israel.

Edomites, rather than Hebrews, were the founders of the future Judah.
This accounts for the comparatively late appearance of Judah as a separate tribe in the history of Israel, as well as for the antagonism which existed between it and the more pure-blooded tribes of the north.
In the Song of Deborah and Barak, Judah is not mentioned; Ephraim and Benjamin, and not Judah, are still regarded as forming the bulwark of Israel against the Amalekite marauders of the southern wilderness.