King David was a young shepherd boy at the time of his encounter with Goliath. He was from the tribe of Judah and was later anointed as king. He was known for his musical talent, playing the harp, and for his great faith in God.
In the beginning, Saul welcomed David into his presence. David's musical talent was a comfort to Saul. But then David's victory over Goliath made him a hero. This new - found fame made Saul feel threatened. Saul's jealousy grew, and he started plotting against David. David had to flee for his life. Despite Saul's attempts to kill him, David still showed respect for Saul as God's anointed. Their relationship was a tumultuous one, full of twists and turns, with Saul's envy driving a wedge between them until Saul's death.
King Saul was the first king of Israel, but he became jealous and disobedient. King David, on the other hand, was known for his faith in God. David was a shepherd boy who became a great king. Saul's downfall was due to his disobedience, while David, though he sinned, always repented and returned to God.
King David's main achievements include establishing a strong and united Israelite kingdom. He was a great military leader and conquered many lands. Also, he was a prolific poet, with the Psalms being attributed to him. Solomon's major achievement was his wisdom. He also built the magnificent Temple in Jerusalem, which was a great architectural feat and an important religious center for the Israelites.
Well, in King David's story, his relationship with Bathsheba is quite a significant event. His lust for her led him to commit adultery and then try to cover it up by having her husband Uriah killed in battle. This was a great sin. Also, his early days as a fugitive from Saul are important. Saul was jealous of David's popularity and tried to kill him, so David had to flee and form his own group of followers, which later helped him in his rise to power.
To be honest, I don't have a definite answer for you on when the story of King David's mother was written. It's a complex matter that involves in-depth study of ancient literature and historical context.