halacha - What was the 'evolution' of determining who is part of the Jewish people?

Starting with Abraham and continuing till modern halacha. how has the halacha regarding who is part of the Jewish people changed? What were the causes of the change, and the reasoning, and the change itself?

I know that today the 'tribe' goes based off the father and the 'Jewishness' is based on the mother. However, that clearly was not the system with tanach, or in the chumash. And the system also changed pre-matan torah and after-matan torah.

I'm looking for 'who' 'when' and 'how' the rules changed over the milenium.

edit: Please don't try to argue that the rule never changed. There are too many stories of non-Jewish women marrying Jewish men with no indication of conversion or statements saying that the children will not be Jewish in tanach. (Like samson and delilah) Clearly the halacha changed, and there is a good reason for it, but I want to know the details of how and when. I am not interested in explanations of 'really, it was always this way'

Answer

As I heard it from a Rabbi Frand tape, and similarly in a shiur from Rabbi Breitowitz:

The question is also raised with regards to Mahlon & Kilyon marrying "Moabite women" in Ruth Chapter 1. If they weren't Jewish, how could they have married them? If they converted, why do we derive the necessary commitment for a convert from what Ruth says after she married Mahlon?

Two answers are given:

• Post Sinai, conversion was always necessary. The sincerity of various conversions was called into question, and Ruth's commitment after-the-fact proves that she really meant it. Her sister-in-law (-in-law) Orpah walked away when Judaism was no longer convenient, which proves her conversion wasn't real. Similarly, if Nach describes someone marrying a "gentile" woman, that's because she went through the motions of a conversion, but we now know looking back that the sincerity of the conversion was a sham.


• The Biblical prohibition on intermarriage applied only to the Canaanite nations, or to acts performed "in public" (as Zimri did). Marrying women from other non-Jewish peoples, if done someplace where no Jews were around, was only prohibited later (I believe this is attributed to the Hasmoneans). Yes, this means the children would not be Jewish. So it was not actually prohibited for Mahlon, living deep out in Moabite-land, to marry Ruth.

So there are three time periods:

• Pre-Sinai: different determination of "who is a Jew?"


• Sinai to Hasmonean: same "who is a Jew" as today, but intermarriage allowed in some cases


• Post-Hasmonean: same system as today; Judaism defined by matrilineal descent or sincere conversion; all intermarriage prohibited