Inspired by a painting of a weary farm worker, a schoolteacher named Edwin Markham sent a poem to a San Francisco newspaper in 1899. The poem, “The Man with the Hoe,” questioned the justice of a world system that required many people to perform “endless, hopeless and joyless labor.” The poem brought a nationwide reaction in an age when most people had memories of working on a farm.
Here is a sample from the poem:

Bowed by the weight of centuries he leans
Upon his hoe and gazes on the ground,
  The emptiness of ages in his face,
  And on his back the burden of the world. […]
Through this dread shape the suffering ages look;
Time’s tragedy is in that aching stoop;
  Through this dread shape humanity betrayed,
  Plundered, profaned and disinherited,
Cries protest to the Judges of the World,
A protest that is also prophecy….
Edwin Markham