Agag in the Bible Encyclopedia - ISBE
a'-gag ('aghagh, or 'aghagh, meaning unknown, possibly
"violent," BDB): A name, or title, applied to the king of the
Amalekites, like Abimelech in Philistia and Pharaoh in Egypt.
It is used of two of these kings: (1) A king of Amalek,
mentioned by Balaam (Nu 24:7) in his blessing of Israel; (2) A
later king, in the days of King Saul (1 Sam 15). Saul was sent
with his army to destroy the Amalekites, who had so violently
opposed Israel in the Wilderness. He disregarded the Divine
command, sparing the best of the spoil, and saving Agag the
king alive (1 Sam 15:8,9). After rebuking Saul, Samuel had
Agag put to death for all the atrocities committed by himself
and his nation (1 Sam 15:32,33).