In Gathering Blue, what did the Song of Ruin tell about and when can it be heard?

The Ruin Song chronicles the history of people and life on earth from the beginning to the present. Because most people in Kira's society are illiterate, the Ruin Song is the way the culture preserves and passes on its history. Once a year, at the Annual Gathering, all the people of the community assemble in the Council Edifice to listen as the official Singer chants and sings the song. The performance lasts the entire day.

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The Ruin Song chronicles the history of people and life on earth from the beginning to the present. Because most people in Kira's society are illiterate, the Ruin Song is the way the culture preserves and passes on its history. Once a year, at the Annual Gathering, all the people of the community assemble in the Council Edifice to listen as the official Singer chants and sings the song. The performance lasts the entire day.

The Ruin Song relates centuries of history. It speaks of the Ruin, an apocalyptic event in which skyscrapers tumbled, cracks appeared in the ground, and explosions and fire lit the sky. Jamison sings part of the song to Kira in chapter 18: "Burn, scourged world,/ Furious furnace,/ Inferno impure." He recites another section that begins "Ravaged all" and lists the names of ruined cities: Bogota, Baltimore, and Toronto. That section shows that large cities on the continents of North and South America were destroyed in the cataclysm.

The Ruin Song depicts what must have been a world war, possibly including the use of nuclear weapons, that destroyed the entire American society and resulted in the loss of technology for Kira's people.