Rise, like lions after slumber,
In unvanquishable number,
Shake your chains to earth like dew
Which in sleep had fallen on you-
Ye are many — they are few.

Shelly’s “Masque of Anarchy” has been a spectral presence for nearly two hundred years, summoned at climactic moments of civil warfare. Composed to memorialize the 1819 Peterloo massacre, the poem commemorates the sixty thousand people who gathered at the very dawn of the industrial revolution to demand a radical expansion of suffrage, especially to those laboring in England’s dark satanic mills. Dozens died, hundreds were wounded.

The poem wasn’t published for over a decade, until the Chartist movement took it up in 1832. Another ten years after that, it became the anthem of an almost nationwide general strike. Participants referred to the time leading up to that moment and the strikes that preceded it as “holy days.”