Some may not agree, however...
It is a Biblical error to call all Israelites as being Jews.
Per the Jewish historian who lived around 100 A.D., Josephus, he stated that the title of 'Jew' is what those returning to Jerusalem from the Babylon captivity called themselves, and the strangers that returned also with them. In The New Testament (KJV) the word "Jew" is often the word Judean per the Greek. Judean is a territorial type meaning, not a bloodline reference. It applied to those who lived in Judea regardless of their birth.
Study of Old Testament history is very important for the Christian also. There are many things written in The New Testament Books that refer back to the Old Testament histories and prophets. One such Bible history about the Jews and Israel I find not that many of my Christian brethren even know about. It is the split of old Israel that God did because of king Solomon falling into his many wives pagan idol worship, allowing it to exist among the children of Israel.
God split old Israel into 2 separate kingdoms starting in 1 Kings 11.
God said He would rend (split) the kingdom in the days of Solomon's son Rehoboam, and take ten tribes out of the hand of his son, and give them to Jeroboam of the tribe of Ephraim. Jeroboam had been setup by Solomon as governor over the ten tribes of Israel in the north portions of the holy land. The main tribes in the south at Jerusalem-Judea were the tribes of Judah and Benjamin. The Levites served both areas, northern ten tribes and Judea, with Solomon reigning from Jerusalem.
Per Genesis 49:10 and 1 Chronicles 5:2, the tribe of Judah was to be the chief ruler, thus David's house of the tribe of Judah was where the inheritance of kings would come. However, notice in 1 Kings 11 that God gave Jeroboam of the tribe of Ephraim to be "king of Israel" over the northern ten tribes. What's going on with that, since Jeroboam was not born of the tribe of Judah, nor house of David?
Later, the two Israelite kingdoms had war against each other, the "kingdom of Judah" became 3 tribes dwelling in the south (Judah, Benjamin, and Levi), with its capital city at Jerusalem. And the "kingdom of Israel" became 10 tribes dwelling in the north, with its capital city at Samaria. These would also be called the "house of Judah" and the "house of Israel" respectively.
Per 2 Kings 17, God scattered the ten tribe "kingdom of Israel" out of the holy land first. They went captive to Assyria and the lands of the Medes by various kings of Assyria, and they never returned as a people. In the days of Josephus (100 A.D.), he said the ten tribes were still scattered beyond Euphrates, and were a great number of people, too many to be numbered.
Then per 2 Kings 17:18 only those of the tribe of Judah were left in the land (Judah being put for the "kingdom of Judah" made up of the tribes of Judah, Benjamin, Levi, and a small remnant of the ten tribes that refused king Jeroboam's calf idols in the north).
These remaining in the holy land of the "kingdom of Judah", or "house of Judah", are those who used to the title of 'Jew', which Josephus said originates from the name of the tribe of Judah.
Many today wrongly preach that all Israelites are Jews, when that does not align with Bible history nor even secular Jewish history by the Jewish historian Josephus. The only reason for that to happen is Biblical ignorance of this Bible history about God splitting old Israel into two separate kingdoms and houses.
Jewish scholars are divided on the topic of what happened to the northern ten tribe "house of Israel" which God scattered first and that were separated from the house of Judah. Some believe they are gone forever, LOST. Others believe the ten tribes will return and be joined by with Judah in final, which actually that is what God's Word does reveal, when Jesus returns.
But where are the ten tribes today? because God's Word does hint to what would happen to them (Book of Hosea, which even Apostle Paul quoted in relation to Christ's Church in Romans 9).