The Samaritans were considered “half-blood” Jews or “mixed” Jews. After the Assyrians invaded Israel, they interbred with the Jewish people (2 Kings 17:24-41). The rift between Israel and Judah occurred sometime in the fourth century BC.
Manasseh (the brother of the high priest) married a Samaritan, and he was expelled from the community. Manasseh responded by building a new temple on Mount Gerazim, rather than Mount Zion.
In 128 BC, John Hyrcanus sent a raiding party and demolished the Temple. Tensions only rose and division only solidified. In the first century BC, the separation only continued. Hartley writes, “The Samaritans developed their own form of the Pentateuch (the extent of their canon), their own liturgy, and their own religious literature.”
Josephus on the Samaritans
Josephus recounts one episode of the Galileans having a custom of travelling through the Samaritan territory for the Jewish festivals. According to Josephus, the Samaritans would even kill travelers going to Jerusalem (Antiquities, 20.6.1). No reason was even given for why the Samaritans killed these Galileans. To put this in modern terms, it would be like a race-lynching. The Galileans went to the authorities (Cumanus), but they were paid off by the Samaritans. As a result, the Galileans gathered a guerilla army to get vengeance, and border wars began back and forth.
To modernize this, walking through Samaria would be like walking through an all-white or all-black neighborhood during the racial tensions of the 1960’s.
Josephus recounts another story about racial tensions (Jewish Wars, 2.12.3-4). Galileans were travelling through Geman (a Samaritan city), and the Samaritan killed a Galilean and “a vast number of people ran together out of Galilee, in order to fight with the Samaritans” (Jewish Wars, 2.12.3). Again, Cumanus denied their pleas for justice, ignoring them. The Jews in Jerusalem decided to march on Samaria “and slew them, without sparing any age, and set the villages on fire” (Jewish Wars, 2.12.4).
Jewish rabbis on the Samaritans
Ecclesiasticus 50:25-26 states, “There be two manner of nations which my heart abhor[s], and the third is no nation: They that sit upon the mountain of Samaria, and they that dwell among the Philistines, and that foolish people that dwell in Sichem.”
The Testament of the Twelve Patriarchs (2nd century AD) states, “‘Sichem’ is the City of Fools, derided by all men” (Testament, Levi. 6).
“‘May I never set eyes on a Samaritan… May I never be thrown into company with him!” (Megillah, 2).
“The daughters of the Samaritans are regarded as menstruants from their cradle” (Mishnah Niddah, 4:1).
Citing rabbinic authorities (Jer. Kilayim, 9:4), Alfred Edersheim writes, “Their bread declared like swine’s flesh; proselytes were not to be received from them; nor would they have part in the Resurrection of the dead.”
The NT on the Samaritans
Jesus’ Jewish opponents asked him, “Do we not say rightly that You are a Samaritan and have a demon?” (Jn. 8:48)
Luke records that the Samaritans didn’t accept Jesus (a Jewish rabbi) when he travelled through their territory (Lk. 9:53).
Jesus didn’t agree with Samaritan beliefs (Jn. 4:22), but he did preach the gospel to even the most rejected of them: the woman at the well (Jn. 4). In fact, when Jesus spoke with the Samaritan woman, she was absolutely shocked (Jn. 4:9). Jesus came to seek and save the lost—not torch them! (cf. Lk. 9:54; 19:10)
Jesus specifically included the Samaritans in the Great Commission (Acts 1:8), and God sent Peter and John to lay hands on them to see them get the Holy Spirit after conversion (Acts 8).
 Nolland, J. (1998). Luke 9:21–18:34 (Vol. 35B, p. 536). Dallas: Word, Incorporated.
 Alfred Edersheim, The Life and Times of Jesus the Messiah (Vol. 1), (New York: Longmans, Green, and Co., 1896), 401.