From about 1500BC to about 1050BC Israel struggled with the JEBUSITES, until David defeated them. David actually turned Jebus, the capital of the JEBUSITES, into the capital of Israel! Jebus is Jerusalem.

During the days of Conquest (Joshua 15:63):
"Now as for the JEBUSITES, the inhabitants of Jerusalem, the sons of Judah could not drive them out; so the JEBUSITES live with the sons of Judah at Jerusalem until this day."

During the entire period of Judges (Judges 3:5)
"The sons of Israel lived among the… JEBUSITES."

At the time of Israel's United Kingdom (2 Samuel 5:6-10):
"Now the king [David] and his men went to Jerusalem against the JEBUSITES, the inhabitants of the land, and they said to David, 'You shall not come in here, but the blind and lame will turn you away'; thinking, 'David cannot enter here.' Nevertheless, David captured the stronghold of Zion, that is the city of David.…So David lived in the stronghold and called it the city of David. And David built all around from the Millo and inward. David became greater and greater, for the LORD God of hosts was with him."

Ephesians 6:12
"For our struggle is not against flesh and blood, but against the rulers, against the powers, against the world forces of this darkness, against the spiritual forces of wickedness in the heavenly places."