At the end of the book Achilles and Agamemnon meet in the underworld and they tell each other how they died. This is important to the story because we finally understand how the Iliad ended. It is also significant because it explains that Agamemnon is happy for Odysseus because he found a loyal wife.
"'For my return Zeus hatched a pitiful death at the hands of Aegisthus and my accursed wife'" (22. 105-06).
This is when Odysseus finally returns home to see his father. His father breaks down at the memory of his son and Odysseus reveals himself to him. Laertes is very happy. This is significant because Odysseus finally returns home to see his family and it is a major moment in his quest.
"A black cloud of grief came shrouding over Laertes... he poured it over his grizzled head, sobbing" (22.356-57).
"'We had high hopes we'd meet again as guests, as old friends, and trade some shining gifts" (22.352-54).
This is the ending of the Odyssey where Athena stops the Ithacans from starting a fight against Odysseus and his crew. She makes peace between the two and the Ithacans all forget about the slaughter of the suitors. All on Ithaca is resolved.
"'Hold back, you men of Ithaca, back from brutal war! Break off- shed no more blood-make peace at once" (22.583-84).