Over the course of U.S. history, the rise of the wealthy and the fall of overall wellbeing were linked.

Inverse relationship between well-being and inequality in American history. The peaks and valleys of inequality (in purple) represent the ratio of the largest fortunes to the median wealth of households (the Phillips curve). The blue-shaded curve combines four measures of well-being: economic (the fraction of economic growth that is paid to workers as wages), health (life expectancy and the average height of native-born population), and social optimism (the average age of first marriage, with early marriages indicating social optimism and delayed marriages indicating social pessimism).

There is an interesting article in Aeon magazine by Peter Turchin that states:

From the Roman Empire to our own Gilded Age, inequality moves in cycles. The future looks like a rough ride.

The graph above is from that article, focusing on the last two centuries in the United States.

One wonders whether the stock market crash in 1929 and the Great Depression led the middle class and the working class to use their numbers to take control of government and use government to reduce inequality. The apparent increase in inequality apparently began with the election of Reagan, and reflected an upsurge in conservative power in government.