since around the time of classical Rome sects of abrahamic monotheism have been disagreeing about what rules "people of the book" should live by. Do we know how many of the commandments (in the old testament or supposed auxiliary texts)pre-Roman conquest Jewish communities actually took seriously?

by grapp
rcxheth

This is actually a matter with which a person who specializes in specializes in Hellenistic/Sectarian Judaism could be quite helpful (while I know a bit, my specialization is a few centuries earlier). Little is known about the various popular Jewish sects of the day. For example, we do not have any primary documents that can be linked directly to the Pharisees or Sadducees.

The material contained within 1-3 Maccabees, though admittedly highly propagandistic in nature, is helpful to an extent. The texts showed a group that was deeply anti-Hellenistic. However, per 1 Maccabees 2, due to their taking of severe losses due to not fighting on the Sabbath, it says that they would forgo choosing not to fight at another point. This is an admission of breaking one of the most important commandments. The Hasmonean Dynasty (composed of the Maccabees) was the primary ruling group in the eastern Mediterranean from about 140-~35 BCE.

This is why the Dead Sea Scrolls are so important. The group responsible for the Scrolls (scholarly consensus tends to drift toward a group called the Essenes) was highly anti-Hasmonean in their rhetoric. For example, most scholars (H. Eshel wrote an entire book on the subject [The Dead Sea Scrolls and the Hasmonean State]; others share her opinion) believe the document 4QTest/4Q175 to be a treatise against the Hasmonean ruler John Hyrcanus. There are several other DSS documents that supposedly have an anti-Hasmonean tone.

I know that I've given you an answer that doesn't touch on the specifics of your question, but it speaks to the fact that there were very serious differences in how to approach the laws of the Torah just within the different forms of Hellenistic (pre-Roman) Judaism.