Inequality in human societies has always existed. When it becomes extreme (that point varies by society and historical circumstances) the society either collapses completely (e.g., revolution, war, failure of basic services, famine) or undergoes changes in its basic framework. Ancient Rome, for example, nearly collapsed when corruption in government and economics (particularly appalling poverty) combined with the refusal of its citizens (particularly the wealthy) to put themselves at risk by organizing to defend it from invading societies (e.g., Goths, Celts). The near collapse extended over three centuries. And even at the end of that time much of Roman culture survived within other societies. Later, the English turned ancient Greek and Roman cultures into idealized prototypes for their empire.
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