Samaritans were Semites, hence rather than say "Jews" I used Semites because not all Semites were Jewish. The Semites migrated to the Levant before 2400 BC.
"According to their tradition (Samaritan), the Samaritans are descended from the Israelites who, unlike the Ten Lost Tribes of the Twelve Tribes of Israel, were not subject to the Assyrian captivity after the northern Kingdom of Israel was destroyed and annexed by the Neo-Assyrian Empire around 720 BCE. Regarding the Samaritan Pentateuch as the unaltered Torah, the Samaritans view the Jews as close relatives but claim that Judaism fundamentally alters the original Israelite religion. The most notable theological divide between Jewish and Samaritan doctrine concerns the world's holiest site, which the Jews believe is the Temple Mount in Jerusalem and which Samaritans believe is Mount Gerizim near modern Nablus and ancient Shechem".
The various "exiles" were never universal. In most of the exiles, the focus was on those most likely to organize resistance to whichever entity conquered Israel. This practice was pretty common at the time, where the conquerors would establish themselves as the "new" upper class and the lower class were comprised of the native populations. You see this in India, where the upper and lower classes have distinct skin color differences because Hinduism strongly discouraged inner class marrying. You even see it in Mexico where the upper class has lighter skin, and the Native American population tend occupy the lower rung of society. The mixed children of Spanish soldiers and Native American women comprise the middle class of many Hispanic nations. Over centuries this racial segregation does breakdown, but how quickly depends on many factors.
There is historically a trend of some conversion from the indigenous religion to that of the conquering one either voluntarily (for religious or economic reasons) or in the case of Islam by decree. Judaism does not promote evangelism; however, it does accept converts.
What makes Judaism so fascinating to study, is that it has survived thousands of years of antisemitism and attempts to eradicate it, which is amazing. Compare that with many other ancient religions like those of the Egyptians, Germans, Celts, etc.
Interestingly, Zoroastrianism, the original religion of the Persians, has begun to rebound in Iran. Do you think Persians will someday reject Islam as the faith of the Arab Conquerors just as Jews in Israel have, even if many Persians remain Muslim? Who has the stronger claim, the mixed Arab/Persian Muslims or the original Perians?
Your Roman conversion number seems off unless you are referring to Roman citizens. By the time of the Empire, "Roman" was a citizenry and not a religion or ethnicity, which is why Paul was both Jewish and Roman. There were very few Romans of Italian origin in Israel. Even the army was not very "Roman" ethnically at the time. So, any reference to Roman does not refer to an ethnicity or even a religion.
What has been historically true including with Vikings, Spanish, Arabs, Romans, Greeks and even the US military stationed in Europe and Asia, is that when armies conquer or occupy other nations, the shortage of women for the soldiers result in them tending to take on native wives. I don't doubt that many Roman soldiers stationed in Israel, who married Jewish wives converted at least on paper, since Jewish doctrine prohibited Jewish women from marrying non-Jewish husbands much as Islamic law does today with Muslim religions.
However, intermarriage does not inherently compromise an ancestral claim. There are three lines of thought regarding land. One was held by groups like the Native Americans and other nomadic people, that no one can "own" land. The other is that land is owned by individuals. And the third is land is owned by identity groups. All of these theories have proponents, but for the most part the only theory that applies today is land belongs to those who can occupy it and defend it. Even in America today, if a person does not occupy and defend his or her property, they can lose it to squatters at the individual level. At the national level, Tibet came under Chinese ownership because they could not defend it.
And so, today both Israel (comprised of Jews, Christians, and Arabs) possess the land. Palestinians many of whom have no direct claim to the land want to possess the land and so each party outlines the basis for their claim trying to twist history to support their argument. But the reality is and always has been possession determines ownership.
Do you think Putin will willingly give back any parts of Ukraine he has seized? How about China and Tibet? Or even the US and Hawaii? Or Poland's occupation of German lands after WW2 or Czech's seizure of German lands after WW2? The whole premise of historical claims has not really shown itself to carry much weight except among identity groups who want to find a "moral" justification for a specific identity group they sympathize with to seize land, they don't occupy.
