What you mean is Joseph wasn't Judah, not that he and the other brothers weren't part of the Israelite monotheistic religion and ethnic nation at that time. All the 12 (+1) tribes were of the same blood, the same background - even if born of several different mothers. They spoke the same language, and kept the same customs. Joseph's sons were, however, half Egyptian. Their mother was the daughter of a High Priest (usually of royal or aristocratic blood). But the adorable boys, Menasseh and Ephraim, became part of Israel and though their descendants, like most of the other tribes, were later lost to the Jewish religion when they were taken into exile by the Assyrians, one can say that they are still basically "Jewish" in as much as the Jews (made up of the tribes of Judah and Benjamin, plus a bit of Dan and other tribes as well, including Menasseh and Efraim!) are part of the Children of Israel, the Tribes of Israel.
Shabbat Shalom Trudy,
I agree that Joseph isn't Judah - they are two distinct tribes, descended from Hebrew brothers - FAMILY.
Some say that Joseph's wife was actually white, aristocratic; others believe Joseph's wife was a daughter of Job who some say was Pharaoh Khufu (if I remember correctly). Remember even Moses was referred to as an "Egyptian" and yet he was a Hebrew! And there are plenty of white Africans today, although folks would assume they were black if they read about them in a newspaper. Regardless, today the Anglo-Saxons alone fulfill all the prophecies about Ephraim and Manasseh, bearing the prophetic birthmarks of our father Joseph (who remained faithful to the God of Abraham, Isaac and Jacob).