Alexei Navalny's memoir "Patriot" will be published posthumously on Oct. 22.
The memoir is compiled from the Russian opposition leader's prison diaries and was edited in part by his widow, Yulia Navalnaya. The book will be released in 22 languages, including Russian.
Navalny died on Feb. 16 in a penal colony in northern Russia, after being convicted in several fabricated criminal cases as part of the Kremlin's crackdown on dissent. Leaders around the world have blamed Russian President Vladimir Putin for his death.
In "Patriot," Navalny wrote that he expected to die in prison.
"I knew from the outset that I would be imprisoned for life — either the rest of my life or until the end of the life of this regime," he wrote in a March 2022 diary entry.
"I will spend the rest of my life in prison and die here."
Navalnaya has said she hopes the memoir ensures that her husband won't be forgotten and that his political activism continues to inspire the Russian opposition movement.
"I want his voice to be heard loudly even after his death," she told the BBC's Russia service in an interview ahead of the book's release.
Navalnaya has accused Putin of murdering her husband and vowed to continue Navalny's political work. A Moscow court ordered her arrest in absentia in July, charging her with "participating in an extremist organization" due to her involvement with the Anti-Corruption Foundation, an organization founded by her late husband.
Navalnaya would "go to the elections as a presidential candidate" if she ever returned to Russia, she told the BBC.
The Kremlin has denied any role in Navalny's death.