What did Ahab do that made God more angry with him than all the kings before him? Here is the full passage of Scripture:
But Ahab son of Omri did what was evil in the Lord’s sight more than all who were before him. 31 Then, as if following the sin of Jeroboam son of Nebat were a trivial matter, he married Jezebel, the daughter of Ethbaal king of the Sidonians, and then proceeded to serve Baal and worship him. 32 He set up an altar for Baal in the temple of Baal that he had built in Samaria. 33 Ahab also made an Asherah pole. Ahab did more to provoke the Lord God of Israel than all the kings of Israel who were before him.
1 Kings 16:30-33 (HCSB)