David the King - Melech Israel

Then all the tribes of Israel came to David at Hebron and spoke, saying, “Indeed we are your bone and your flesh. Also, in time past, when Saul was king over us, you were the one who led Israel out and brought them in; and the Lord said to you, ‘You shall shepherd My people Israel, and be ruler over Israel.’ ” Therefore all the elders of Israel came to the king at Hebron, and King David made a covenant with them at Hebron before the Lord. And they anointed David king over Israel. David was thirty years old when he began to reign, and he reigned forty years. In Hebron he reigned over Judah seven years and six months, and in Jerusalem he reigned thirty-three years over all Israel and Judah.
2 Samuel 5:1-5