Levelling
There is every reason to believe that for the first couple of hundred thousand years of human existence all people lived in mobile hunter-gatherer bands. There is considerable evidence that all, or nearly all, such bands encountered in historic times practiced some sort of redistribution, usually by sharing large kills. There is indirect but persuasive evidence that this practice is of great antiquity (large kills show evidence of being butchered by a single individual). This kind of sharing produced highly egalitarian societies. When people settled down, either because of concentrated local food resources or agriculture, this changed. Societies became stratified and unequal. Nobles, princes and social classes rapidly become entrenched. The transformation seems to have been triggered by the invention of property. In a mobile HG band, property is what you can carry, and nobody has enough to be jealous of, or if you are jealous of it, you probably won't be able to carry it.