Austin Allen in Book Think:
“Poets are the unacknowledged legislators of the world,” Percy Shelley wrote in 1821. Not surprisingly, this claim has earned some snickers from people who think of poets as barely able to legislate their own grooming habits. Fellow writers have made fun of it, too: in the twentieth century Auden shot back, “‘The unacknowledged legislators of the world’ describes the secret police, not the poets.”
But Shelley was speaking metaphorically, of course, and also fairly broadly; his general point was that language is the decisive force in human affairs. Culture, religion, and politics derive from narrative, myth, and rhetoric—and all of these things derive from “poetry,” that is, memorable figurative language.
Even if you interpret Shelley’s words in the narrowest sense possible—“Verse writers are the secret movers and shakers of global politics”—you’ll find that Shelley himself, more than almost anyone else, has proven them true. Don’t believe me? Look up his poem “The Masque of Anarchy,” which, although now largely forgotten, has sparked some of the most sweeping historical changes of the past two centuries.
“Masque” was written in response to the Peterloo Massacre of 1819, in which British troops attacked a defenseless crowd of citizen protesters. The poem urges the “Men of England” to rise up—and stand still—against tyranny:
Let a vast assembly be,
And with great solemnity
Declare with measured words that ye
Are, as God has made ye, free.
…
Stand ye calm and resolute,
Like a forest close and mute,
With folded arms and looks which are
Weapons of unvanquished war,
And let Panic, who outspeeds
The career of armed steeds
Pass a disregarded shade
Through your phalanx undismayed.
More here.