Now when day came, there was no small stir among the soldiers over what had become of Peter. And when Herod had sought for him and could not find him, he examined the sentries and ordered that they should be put to death. Then he went down from Judea to Caesare'a, and remained there. Now Herod was angry with the people of Tyre and Sidon; and they came to him in a body, and having persuaded Blastus, the king's chamberlain, they asked for peace, because their country depended on the king's country for food. On an appointed day Herod put on his royal robes, took his seat upon the throne, and made an oration to them. And the people shouted, "The voice of a god, and not of man!" Immediately an angel of the Lord smote him, for he did not give God the glory; and he was eaten by worms and died.
Let us think about Luke's story and why he wanted to include the death of Agrippa. It is told in the context of Peter going into hiding. When we hear "then he went down from Judea to Caesarea" we might easily think that Luke was writing about Peter going to hide at Cornelius' house. But since Agrippa died at Caesarea in 44AD, in the midst of a festival, it seems likely that Luke is referring to the King and not just to the fugitive. Peter went into hiding at a time when the Gospel was being received by Gentiles. This was a joyous moment and we still thank God for making it possible. Yet,, it happened under very strained and tenuous circumstances and raised new problems. Life was difficult enough for believers in Jerusalem without their being exposed to accusations by "the circumcision party". "The Jews" seem to have had detailed knowledge about the way the Christian Jews related to Gentiles in Gentile regions. So it would be hard to escape the rampaging Agrippa. Still, no matter who was King in Judaea, those who believed in Jesus had a responsibility to tell all their neighbours, including Jewish ones, that they need wait no more. The Promised One had come.
We cannot know for certain the exact chronology of these events. But the problems with interpreting different texts (eg Acts and Galatians) and relating them to each other may also have been Luke's problem as he worked out how he was going to describe the "flow of events". We know Paul confronted Peter in Antioch (Galatians 2:11). Was Luke "back-tracking" in his narrative at 11:19-26 to explain to us that Cornelius had already heard the gospel sometime after the persecution began from the preaching to the Gentiles? If so, he is saying that God had arranged things so that the issue of table fellowship with Gentiles had already been decided well before the events described in Acts 15 or the writing of the letter to the Galatians. And in fact they had been. Peter's confrontation with Paul confirmed Peter in the views he had been given in his dream. The "apostles and brethren in Judea" were overjoyed to hear of the "Gentile repentance unto life".
Agrippa was a dangerous thug of a ruler. He murdered James and imprisoned Peter. But before he knew it he was struck down. The Herodians and other groups that wanted to use their influence at court to oppose the Christian movement lost some leverage for a time. The administration reverted to a Roman Procurator.