During the Republic, the basic legal code was the Laws of the Twelve Tablets. Over the years these laws (and we don't know all of them) were reinterpreted, changed, and loopholes were found, but the basic rights of an individual remained the same.
It was called the Torah (תורה)
It was God who "came up with" the Torah, not the Hebrews.
They were first called Ivrim (עברים) which means "Hebrews"
Hebrews did not hunt. They followed a dietary code that required special slaughtering of animals.
The laws of the Byzantine legal system were rewritten under the Emperor Justinian I and the reformed code was called the "Codex Justinianus." It was one of the four parts of the Corpus Juris Civilis, a comprehensive compilation of Roman laws.
Justinian Code
By the time there were Christians, the Hebrews were no longer called Hebrews. They were called Jews. Christians didn't give them this or any name.
Israel is the home of Hebrews, but they are actually called Jews.
Judaism. And today we no longer prefer the name Hebrews. Rather, we're called Jews.
The Ancient Hebrews are called Jews today.
Yes, there is a book in the New Testament called "Hebrews"