From reader Jon Lewis:

I noticed with great interest your Volokh post on the ethnic background of some of the Arabs in the Galilee. I have been writing on ethnicity and minority rights in the Middle East for the Wall Street Journal and the Middle East Quarterly for several years....

In response to your query : I would say that you touched on a very important, but neglected story in Middle Eastern history. In 1830, following the French colonial takeover of Algeria, the Algerian-Sufi rebel leader Abdel Qader who lost his battle with the French, made a deal with the Ottomans to move (along with his followers) to the Galilee of what was then called "Syria." There is good archival material in France showing how many of the Arabs of the Galilee are descendents of Abdel Qader's followers. Some of the Arabs with African features may be of Algerian Tuareg (southern Algerian) ancestry. There was also immigration in the early 20th-century of Chadian Muslims from Chad to Jerusalem who stopped in Jerusalem (or al-Quds as they would term it) after Hadj to Mecca. It is possible that some of these clans moved outward to the Galil.

Amazing what one can learn from blogging!