Ephraim, Ephraimite, Ephraimites

Facts:

Ephraim was the second son of Joseph. His descendants, the Ephraimites, formed one of the twelve tribes of Israel.

The tribe of Ephraim was one of the ten tribes that were located in the northern part of Israel.
Sometimes the name Ephraim is used in the Bible to refer to the whole northern kingdom of Israel. (See: rc://en/ta/man/jit/figs-synecdoche)
Ephraim was apparently a very mountainous or hilly area, based on references to "the hill country of Ephraim" or "the mountains of Ephraim."