When, after thirty years of struggle, the abolitionist movement finally achieved victory, Garrison was invited to speak before Northern soldiers. Yet even in this speech he refused to surrender his commitment to freedom to political power. Addressing the soldiers and politicians present, he said, in the Persian rendering preserved here:

“I have not come here to pay homage to any flag except the flag of freedom. If your Union is not a symbol of the liberation of all human beings throughout the world, I am not united with it. If your Constitution does not guarantee the freedom of every human being, I will not be loyal to that Constitution. And if there is a single drop of the blood of an enslaved human being upon your flag, I reject the legitimacy of that flag in the name of God. I have come here to witness the raising of a flag that recognises the existence and freedom of all human beings wherever they may be. I regard myself as a lover of freedom so radical that my dream is the abolition of every prison in the world. I know this dream is very distant, but I know that one day it will arrive with human freedom and intellectual maturity. My fellow citizens and my brothers: every right that belongs to us belongs to every other human being as well, and our duty is not merely to understand and accept that right, but to struggle for its realisation.”

After the victory of the abolitionist movement, Garrison stopped publishing The Liberator. In its final years the newspaper had loyal subscribers not only throughout the United States but also in Canada, England and Scotland. In his last editorial William Garrison wrote, in the Persian rendering preserved in this source:

“The purpose for which The Liberator began thirty-five years ago has been brought with honour to its conclusion. This is the final issue of the newspaper, but the ideals of freedom have not ended. By ending this newspaper I close it as a chapter in the turbulent history of freedom, for future generations to read if they wish, and I hope others will open new chapters. Without doubt I will continue to be present in these struggles until the end of my life—struggles in which, instead of hundreds, we will see millions beside us. In closing, allow me to give you a principle that has always, at every moment, filled my life with passion and meaning:
‘Freedom for every human being; freedom for all; freedom everywhere. This will remain our ideal and the ideal of tomorrow’s generations of freedom fighters.’”

William Garrison died on 24 May 1879. At a funeral where hundreds of Black and white women and men, Native Americans and civil-rights activists gathered to honour his life and say farewell, he was buried at Forest Hills beside his wife Helen, herself committed to freedom and a companion in the struggle throughout those years.

He was a man who lived his entire life by the ideal:
“My country is the whole earth, all people are my brothers, and my religion is doing good to humanity. Every right that belongs to me belongs to every other human being as well, and my duty is not merely to understand and accept this truth, but to struggle for its realisation.”