According to Flavius Josephus: "...the entire body of the people of Israel remained in that country; wherefore there are but two tribes in Asia and Europe subject to the Romans, while the ten tribes are beyond Euphrates till now, and are an immense multitude, and not to be estimated by numbers." -Antiquities of the Jews (Book XI Chapter 5 Section 2)
Note that when Josephus mentioned "Asia", he was referring to Asia Minor or modern-day Turkey. In general, he made a semi-veiled reference to the Ten Tribes of Israel being located in Parthian territory, Rome's arch rival across the Euphrates River, the de facto border between the two empires. He did not need to say "Parthia". Everyone during his time knew what he was referring to in the same way people living in California today would not need a description of what is "east of the Mississippi River" or what is "south of the Rio Grande". Yet, for those who understand the extreme fluidity of the Middle East and Central Asia, it begs the question: "Who are the Parthians today?" ...or rather: "Where did the descendants of Parthia and related Saka-Scythian peoples go in later centuries?"
Because of numerous circumstances that led up to and followed the collapse of the Parthian Empire in the 3rd Century CE, we believe most of the evidence indicates some of their descendant population remained in Asia, but much of it (and closely related groups surrounding Parthia) expanded into Europe and deeper into India during the time period known as the Great Migration. For more evidence, see: Israelite Haplogroup (DNA) Hypotheses.
WHERE WERE THEY ORIGINALLY DEPORTED?
Parthians (non-Persian) are generally believed to have been of Scythian-stock. Scyth, Saka, and/or Sacae are names given to a large grouping of peoples that may or may not have been genetically related, but interestingly, their broader populations sprung up in the very areas 10-Israel were deported. If the Scythians were not fully Israelite (Hebrew), they were certainly made up of Israelite population groupings to some degree. They were not "Persian" for the Persians were subjugated by the Parthians for over 400 years during their rule and the Persian (Sassanid) returning kings had an aggressive effort to conquer Parthian-Scytho peoples who were fleeing in multiple directions (partially contributing to the Great Migration period of Caucasian peoples into Europe). Note: the details of the fall of Parthia and second great rise of Persia is not well-known (Frye, 461) and surrounded with much controversy in general.
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