Who was King Nadab in the Bible

Nadab was a King of Israel who succeeded his father Jeroboam to reign over the northern kingdom of Israel. He reigned for only two years before he was assassinated by Baasha bringing an end to the Jeroboam’s dynasty.

Baasha killed Nadab in the third year of Asa king of Judah and succeeded him as king. 1 KINGS 15:28

The dynasty of Jeroboam, king of Israel, came to an abrupt end with his son Nadab in the late tenth century BC.
More than twenty years before Nadab’s reign, his father Jeroboam had revolted against Solomon. According to the prophet Abijah, God intended to punish Solomon’s idolatry by cutting his kingdom in two.
The northern portion, Israel, would go to Jeroboam, who was offered the chance to build a lasting dynasty to match David’s—if only he would devote himself fully to God.
Nadab’s father, however, had other plans. He reasoned that if his people continued to worship the Lord which meant recurring trips to the temple in Jerusalem, the capital of the southern kingdom their loyalties would eventually revert back to the line of David. So Jeroboam made two golden calves for Israel to worship, setting a precedent that would haunt the country for the remainder of its days.
As a result, Jeroboam forfeited the prospect of a lasting dynasty his family’s hold on power ended with the brief tenure of Nadab.
Jeroboam’s son reigned for just two years. While attacking a Philistine stronghold in the southwest part of his kingdom, Nadab was assassinated by a man named Baasha very likely one of Nadab’s own military commanders. Unlike the kingdom to the south, there would be no lasting dynasty for the northern kingdom of Israel.
Nadab means “noble” in Hebrew, an ironic name for someone who “did evil in the eyes of the LORD” (1 Kings 15:26). He shared his name with one of Aaron’s sons, a priest who was struck down for offering “unauthorized fire” to God (see Leviticus 10:1).