Short answers, pulled from the story.
Hesiod wrote Works and Days in the late 6th century BCE to introduce a cycle of five human ages describing temporal decline. The first age was Gold where people lived like gods without sorrow or grief while the earth produced food abundantly.
Plato discussed the golden race of humans in Cratylus around 397 e. He clarified that Hesiod did not mean literally made of gold but good and noble.
A tradition arose in Greece linking Arcadia to the original Golden Age site as an impoverished rural area where herdsmen lived on acorns. The goat-footed god Pan dwelt among poplars on Mount Maenalus there.
Hindu culture viewed history as cyclical with four yugas corresponding to Greek ages where Satya Yuga represented the Golden Age. Most people engaged only in good deeds during Satya Yuga times while men neither bought nor sold because all needs obtained through power of will.
J.R.R. Tolkien designed Arda symmetrical and perfect in The Silmarillion before wars changed its shape. Arda Unmarred later became known as Arda Marred following divine conflicts.