The years from the late 19th and early 20th centuries were not the most egalitarian in American history. Robber barons roamed the economy, living off lavish rents generated by powerful cartels and industrial monopolies.

The richest 1 percent of Americans reaped nearly one in five dollars generated by the economy and amassed almost half its wealth; at the other end of the scale, wage earners lost ground to inflation. It was the era of the Haymarket riots and Upton Sinclair’s “The Jungle.” Workers staged 1,500 strikes in 1886 alone.

Ultimately, though, the disparities in wealth and income led to an age of ferment that came to be known as the Progressive Era.

Women got the right to vote. Congress passed the Sherman Act. Chicago’s Beef Trust and John D. Rockefeller’s Standard Oil were taken down. In 1914, Henry Ford decided to raise wages to $5 a day, doubling at a stroke most of his workers’ pay.