Where did the Samaritans originate?

Where did the Samaritans originate?

A simple web search or glance through an encyclopedia will tell that Samaritans came from the ancient city Samaria, located in an area which was called Canaan until Christians and Muslims began calling it...Palestine.
So I guess the simplest to your question would be: Samaritans were from Palestine.
FYI -
King Omri built Samaria in about 800 B.C. and made it the capital of the kingdom of Israel.
In 331 B.C., the city fell to Alexander the Great.
Saint John the Baptist is allegedly buried in Samaria.
-- The term "Palestine" is far older than Christians and Muslims - it was the Roman name for the province, ruled by Herod, containing what is now Israel (and much more). BTW, Zionist publications before WWII and the creation of the state of Israel refered to the Jews living there as "Palestinians"!
The word Palestine comes from L.
Palestina (name of a Roman province), from Gk. Palaistine (Herodotus), from Heb. Pelesheth "Philistia, land of the Philistines."