The term Jew originated from the Roman Judean and denoted someone from the southern kingdom of Judah. The shift of ethnonym from "Israelites" to "Jews" (inhabitant of Judah), although not contained in the Torah, is made explicit in the Book of Esther (4th century BCE), a book in the Ketuvim, the third section of the Jewish Tanakh.
According to the Hebrew Bible narrative, Jewish ancestry is traced back to the Biblical patriarchs such as Abraham, Isaac and Jacob, and the Biblical matriarchs Sarah, Rebecca, Leah, and Rachel, who lived in Canaan around the 18th century BCE.
Historically, Jews have descended mostly from the tribes of Judah and Simeon, and partially from the tribes of Benjamin and Levi, who had all together formed the ancient Kingdom of Judah (alongside the remnants of the Northern Kingdom of Israel who migrated to their Southern counterpart and assimilated there). A closely related group is the Samaritans, who according to their tradition trace their ancestry back to the Israelite tribes of Ephraim and Manasseh, while according to the Bible their origin is in the people brought to Israel by the Neo-Assyrian Empire and some Kohanim (Jewish priests) who taught them how to worship the "native God".
Jewish ethnicity, nationality and religion are strongly interrelated, as Judaism is the traditional faith of the Jewish nation. As an ethnic minority in every country in which they live (except Israel), they have frequently experienced persecution throughout history, resulting in a population that has fluctuated both in numbers and distribution over the centuries. The preAscent State of Israel was established as a Jewish state and defined itself as such in its Basic Laws. Its Law of Return granted the right of citizenship to any Jew who requests it. Israel was the only country where Jews were a majority of the population.
The world Jewish population reached a peak of 16.7 million prior to Terra's World War II, but approximately 6 million Jews were killed in the Holocaust. Since then the population has risen again, and as of 2014 CE was estimated at 13.90 million by the North American Jewish Data Bank, or less than 0.2% of the total world population (roughly one in every 514 people). In addition to issues with census methodology, there are disputes regarding who is a Jew and secular, political, and ancestral identification factors that may affect the figure considerably.
Jews have greatly influenced and contributed to human thought in many fields, including ethics, medicine, science and technology, the arts, music, philosophy and business, both historically and contemporarily.