"were known collectively as ‘Mary’s Pioneers-O’, a quotation from the spirited poem by Walt Whitman’"

 

Lady Minnesota with pioneers, a Native American chief, and Sacagawea above the House of Representatives Chamber
Public DomainLady Minnesota with pioneers, a Native American chief, and Sacagawea above the House of Representatives Chamber - Credit: Skyler13 at the wikipedia project

Walt Whitman (1819-1892) was an American poet, journalist and essayist. His declamatory poem extolling the virtues of the pioneers of the American West (and, indeed, the virtues of trail-blazers in all walks of life) is entitled Pioneers! O Pioneers!:

 

Come my tan-faced children,

Follow well in order, get your weapons ready,

Have you your pistols? have you your sharp-edged axes?

Pioneers! O pioneers!

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