Final answer:
In the biblical book of Samuel, Saul became the first king of Israel but failed to rule properly. David succeeded Saul as king.
Step-by-step explanation:
In the biblical book of Samuel, it is mentioned that Saul became the first king of Israel around 1030 BCE but failed to rule properly. Later, Saul's former lieutenant, David, became his successor. While it is not explicitly stated in the Bible whether God regretted making Saul king, it can be inferred from the narrative that God was displeased with Saul's actions and eventually chose David as the next king.