There are specific modern nations of this world identified as the tribes of Israel.
Manasseh and Ephraim: The tribes of Manasseh and Ephraim are clearly and exhaustively identified by the late Herbert W. Armstrong’s book, United States & Britain in Prophecy.
Manasseh is dominant in the United States, and Ephraim basically constitutes the Anglo-Saxon, English-speaking member countries of the British Commonwealth, such as England, Canada, Australia, and New Zealand, as well as a part of South Africa.
By examining biblical and secular history, the other tribes may be located as follows:
Dan: Ireland and Denmark
Benjamin: Norway and Iceland
Zebulun: Holland (the Netherlands)
Asher: Belgium and Luxembourg
Levi and Simeon: Scattered among the other Israelite nations
Judah, Benjamin, and Levi: The Jews were of the tribes of Judah, Benjamin, and Levi. Some of the descendants of Israel (Jacob) also comprised the nation of Judah, distinct from the nation of Israel. The nation of Israel today, however, is made up mostly from the descendants of Judah.
Gentiles have also settled among these nations, especially in larger cities. The identities of all Gentiles are not given, though we know the Bible identifies Assyria as modern-day Germany. Many of the Chinese and Russian peoples can be traced in chapters 38 and 39 of Ezekiel.