The following was gleaned from articles on Samaria, Samaritans and Palestine in the 2002 World Book Encyclopedia:
Until about 1029 B.C., the Israelites were loosely organized into 12 tribes. The constant warfare with neighboring peoples led the Israelites to choose a king, Saul, as their leader. Saul’s successor, David, unified the nation to form the Kingdom of Israel, about 1000 B.C. David established his capital in Jerusalem. His son, Solomon, succeeded him as king and built the first Temple for the worship of God. Israel remained united until Solomon’s death about 928 B.C. The northern tribes of Israel then split away from the tribes in the south. The northern state continued to be called the kingdom of Israel. The southern state, called the kingdom of Judah, kept Jerusalem as its capital. In about 800 B.C., the king of the kingdom of Israel, King Omri, built the city of Samaria. He made it the capital of the kingdom of Israel. The city of Samaria was about 40 miles north of Jerusalem. The region surrounding the city became known as Samaria. The region of Samaria was situated in the region today known as the West Bank in modern Israel.
During the 700’s B.C., the Assyrians, a people who lived in what is now Iraq, extended their rule westward to the Mediterranean Sea. The Assyrians destroyed the kingdom of Israel in 721 or 722 B.C. and took the ablest Israelites to Assyria as captives. The Assyrian ruler then forced people from eastern Assyria to settle in the region of Samaria. The new settlers brought their own religious ideas, but also sought to please “the god of the land.” Many of them intermarried with the remaining Israelites. People with this mixed ancestry and mixed religion came to be called Samaritans.
The Samaritans adopted the Torah, the first five books of the Hebrew Bible, as their scripture. But the Hebrews to the south refused to associate with them and considered their religion inferior. When the Hebrews rebuilt their temple, they refused help that the Samaritans offered. Eventually, the Samaritans built a temple of their own, but it was destroyed by the Jews in 128 B.C.
In Jesus’s time, the Jews looked down on the Samaritans as foreigners.