Saul was a biblical person mentioned in 1 Samuel of the Hebrew and Christian Bible.
Role in the Bible
Sometime after the era of the judges, the people of Israel approached Samuel - a prophet and the final judge over Israel - that they desired a king much like the neighboring countries. In 1 Samuel, God made him the first king of Israel. According to scripture, Saul was born to Kish and was of the Tribe of Benjamin. Despite initially being reluctant, he accepts his call, and Samuel anoints him as the first king of Israel.
He started out as a great ruler, but he later started to stray away from God. For example, in 1 Samuel 10:8, Samuel told him to wait seven days for his instructions while he goes to prepare a sacrifice. However, due to the fear of the war, he sacrificed offerings to God. Samuel arrives and rebukes Saul for what he had done. As punishment, his kingship would be taken away from him. Saul is also notorious for the repeated attempts he had made on David's life.
In one instance, Saul gives David a seemingly impossible task of going to a town to slay a thousand Philistines and then bring them the foreskins as proof. He would in exchange give his daughter into David's hand for marriage. Unfortunately for him, David succeeds at this task, and he respected his part of the deal. Saul's hatred for David reached its umpteenth when David was receiving praise for killings tens of thousands of Philistines. Out of anger, he tried to strike David with a javelin as David was playing for him. This eventually leads to David going into hiding from the mad king. When Saul went to relieve himself in a cave, he is confronted by David who explains to him that he was that close to killing him, but he otherwise did not because he knew he had God's anointment.
Saul eventually redeems himself and commits suicide at the Battle of Gilda while at the peak of the Philistine army. The Bible has hinted that he was tormented by an evil spirit.