To whom does the champion in this poem refer?

William Lloyd Garrison.

Explanation:

John Greenleaf Whittier wrote his "Anti-Slavery Poems  To William Lloyd Garrison" about the courage and acts of the person. Garrison was an American abolitionist who worked hard for the rights of the oppressed black people/slaves.

In the poem, Whiitier wrote Garrison was "CHAMPION of those who groan beneath Oppression’s iron hand". He further adds

"Go on, the dagger’s point may glare  

 Amid thy pathway’s gloom;  

The fate which sternly threatens there  

 Is glorious martyrdom!  

Then onward with a martyr’s zeal;        

 And wait thy sure reward  

When man to man no more shall kneel,  

 And God alone be Lord! "

The whole poem talks of his admiration for the man, the bravery and courage of Garrison in addressing the oppression of the blacks. The word "Champion" is the very first word in the poem, addressed and referring to William Lloyd Garrison.

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