Israel was unified under King David who was the second king in Israel and was responsible for establishing Jerusalem as Israel's national capital. This was extended until King Solomon, David's successor. After 200 years during Solomon's death, they were divided. After which, they have been rules by outsiders for 300 more years.
The correct answer to this open question is the following.
David and Solomon unified ancient Israel. According to Kings 11:10-13, 43, it was God who said that the kingdom of Solomon would be divided after the death of Salomon. When he died he was buried next to David, his father. After the death of Solomon, the 12 tribes of Israel were divided. The Kingdom of Judah established in the south of the territory. Rehoboam -son of Solomon- was the king of the Jews. In the north, it was the Kingdom of Israel that established there, ruled by Jeroboam. Approximately in 722 BC, the Assyrians invaded Israel and in 586 BC, the Babylonians invaded Judah.
