Final answer:
The quarrel between Agamemnon and Achilles during the war was caused by Agamemnon insulting Achilles by taking his war prize, leading to a heated argument and Achilles' withdrawal from battle.
Step-by-step explanation:
The quarrel between Agamemnon and Achilles in the context of the war can be traced back to the events depicted in Homer's Iliad. Agamemnon, the leader of the Greek forces, insulted Achilles by taking his war prize, a girl named Briseis. This act of disrespect caused Achilles to withdraw from battle and refuse to fight alongside the Greeks during the Trojan War.
Achilles' grievances against Agamemnon stemmed from his pride as a warrior and his sense of honor. He felt dishonored and disrespected by Agamemnon's actions, which led to their heated argument and eventual separation on the battlefield.