From the 1852 speech by Frederick Douglass, reproduced in The Nation some years ago:
I am not included within the pale of this glorious anniversary! Your high independence only reveals the immeasurable distance between us. The blessings in which you, this day, rejoice, are not enjoyed in common. The rich inheritance of justice, liberty, prosperity and independence, bequeathed by your fathers, is shared by you, not by me. The sunlight that brought life and healing to you, has brought stripes and death to me. This Fourth [of] July is yours, not mine. You may rejoice, I must mourn. To drag a man in fetters into the grand illuminated temple of liberty, and call upon him to join you in joyous anthems, were inhuman mockery and sacrilegious irony. Do you mean, citizens, to mock me, by asking me to speak to-day?
More here. [Thanks to Anjuli Fatima Raza Kolb.]