Judges 11:2
And Gilead’s wife bare him sons; and his wife’s sons grew up, and they thrust out Jephthah, and said unto him, Thou shalt not inherit in our father’s house; for thou art the son of a strange woman. And Gilead’s wife bare him sons; and his wife’s sons grew up, and they thrust out Jephthah, and said unto him, Thou shalt not inherit in our father’s house; for thou art the son of a strange woman.
Jephthah was thrust out by his half-brothers, the sons of his father's wife, who denied him any share of inheritance in his father's house. That expulsion forms the setting for his later emergence as the Gileadite deliverer, when he took leadership in the war against the Ammonites and broke their power. This victory came after Israel had endured eighteen years of oppression.