In the days after the Chinese writer and dissident Liu Xiaobo was awarded the Nobel Peace Prize, on Oct. 8, 2010, his country cut off trade talks with Norway, home of the Nobel committee, and placed his wife under house arrest. In apparent protest of the award, a group of Chinese business and cultural leaders established an alternative to the Nobel, the Confucius Peace Prize, and later honored such human rights renegades as Vladi­mir Putin, Fidel Castro and Robert Mugabe.

Mr. Liu, who died July 13 at age 61, received the Nobel for what the award committee called his “long and nonviolent struggle for fundamental human rights.” It was that very struggle, from his hunger strike at Beijing’s Tiananmen Square to his insistent calls to end one-party rule, that also made him a marked man in China.

[Chinese Nobel laureate Liu Xiaobo called ‘a monument to morality’]

He was in the midst of an 11-year prison sentence when he won the prize. It promoted a man whom much of the world regarded as a distinguished activist and whose own leaders considered a dangerous subversive.

Foreign news reports about the Nobel honor were blacked out in China, where authorities called it a “desecration” of the prize. Text messages that included his name went unreceived, stymied by state-run cellular networks, and the news was squelched online by the censorship apparatus known as the “Great Firewall.”

Liu Xiaobo in 2008. (Associated Press)

At the Nobel ceremony in Oslo, Mr. Liu was represented by an empty chair. Not since the 1935 prize, when German pacifist Carl von Ossietzky was being held at a concentration camp by the Nazis, had a laureate or a family member been unable to accept the honor in person. Ossietzky died at a Nazi hospital in 1938.

Mr. Liu spent much of the past three decades in forced confinement — at home, at labor camps or in prison. And his final months, after being diagnosed with late-stage liver cancer in May and granted medical parole, drew international calls for his release.

His death, at a hospital in the northeastern city of Shenyang, was confirmed by a statement from the Chinese government, and it made Mr. Liu the latest in a string of Chinese dissidents whose incarceration ended in serious illness or fatality. A photograph posted July 5 on Twitter by the dissident writer Ye Du showed an emaciated Mr. Liu at the hospital with his wife, Liu Xia, a photographer and poet who had pleaded for better medical care for Mr. Liu.

A pair of American and German doctors who were granted permission to treat Mr. Liu said Sunday that he was strong enough to seek medical treatment abroad. Chinese officials resisted that claim and rebuffed requests from Germany and the State Department to allow him to leave the country.

The hospital treating Mr. Liu said that he was suffering from respiratory and renal failure, as well as septic shock, and that his family had decided against inserting a breathing tube necessary to keep him alive.

Through it all, Mr. Liu’s plight remained largely invisible at home, where his writings were censored and he was labeled a mere criminal.

‘Looking for real life’

A bespectacled chain-smoker with a stutter, Mr. Liu established himself as a literary and political bomb thrower in the mid-1980s, when Chinese society experienced a “cultural fever” under reform-minded Communist Party officials.

Liu Xiaobo in 2008. (Associated Press)

Mr. Liu (whose full name is pronounced lee-oh SHEEOW-bwoh) “was the enfant terrible of the late-’80s intellectual scene in Beijing,” said journalist Orville Schell, an acquaintance of Mr. Liu’s who is now a China scholar at the Asia Society in New York. “He was somebody who you invited to a party with some trepidation, because he was bound to offend someone.”

Confucius was “a mediocre talent,” Mr. Liu said; contemporary Chinese writers were even worse. The country’s “Marxism-Leninism,” he wrote in one article, was “not so much a belief system as a tool used by rulers to impose ideological dictatorship.”

Mr. Liu was a visiting scholar at Columbia University when, in April 1989, thousands of students began demonstrating in Tiananmen Square to demand democratic reforms. The assembly marked a turning point for Mr. Liu, who arrived at Tiananmen in May and began protesting alongside the movement’s young leaders.

When the chants began to die down and soldiers started trying to clear the square, Mr. Liu and three friends — including Hou Dejian, a popular rock singer from Taiwan — erected a tent beside the 10-story Monument to the People’s Heroes and began a 72-hour hunger strike.

“We are not in search of death; we are looking for real life,” the strikers declared in a statement. “We want to show that democracy practiced by the people by peaceful means is strong and tenacious. We want to break the undemocratic order maintained by bayonets and by lies.”

Two nights later, military units launched a full-scale assault on the square, firing their rifles and driving armored vehicles into crowds that lined the surrounding streets. Mr. Liu and his fellow hunger-strikers, fearing a bloodbath in the square, acted as negotiators between military forces and the remaining demonstrators. At dawn on June 4, the group successfully persuaded the students to leave.

Mr. Liu’s actions — at one point he grabbed a rifle from a demonstrator and smashed it on the ground, preventing what he saw as an excuse for the military to “gun everybody down” — were widely credited with saving thousands of lives. Still, at least several hundred civilians were killed in the attacks, details of which were suppressed by the Chinese government.

“From the moment I walked out of the square, my heart has been heavy,” Mr. Liu said in “The Gate of Heavenly Peace,” a 1995 documentary that took its name from the English translation of Tiananmen. “I’ve never gotten over this.”

While biking on June 6, 1989, amid a government crackdown that led other prominent demonstrators to go into hiding, Mr. Liu was captured by Chinese officers. He later recalled the event in a poem, “Experiencing Death”:

Deep in the night, empty road

I’m biking home

I stop at a cigarette stand

A car follows me, crashes over my bicycle

some enormous brutes seize me

I’m handcuffed eyes covered mouth gagged

thrown into a prison van heading nowhere

He was imprisoned for 21 months, branded a “black hand” and an “evil mastermind,” and forbidden from publishing in China — a dictate that he subverted through pseudonyms and by penning articles for overseas publications.

Mr. Liu published more than 1,000 essays, by his count, and called for reform, not revolution. Yet he remained under state surveillance and in 1996 was sentenced to three years of forced labor for drafting a declaration that called for reconciliation with Taiwan, freedom for Tibet and the impeachment of President Jiang Zemin.

Instead of leaving the country, Mr. Liu chose to remain in China, a decision that “was the path of destruction for his life” but that enabled him to remain an effective critic of the state, Schell said. His work culminated in Charter 08, a sweeping, pro-democracy manifesto that landed him in prison for the last time.

Published online in 2008, the document was modeled in part on Charter 77, an anti-Communist tract that Czech dissidents such as Vaclav Havel, a friend of Mr. Liu’s, had drafted decades earlier. Mr. Liu was among the leading drafters and first signers of Charter 08, which called for “the democratization of Chinese politics” through the establishment of a new constitution, greater freedom of expression, an independent judiciary and an end to one-party rule.

The document drew unexpectedly wide-ranging support, receiving 10,000 signatures from farmers, lawyers, philosophers and street vendors until it was pulled off the Internet by Chinese censors. “Probably the most worrying thing to the authorities was the broad coalition of people who decided to put their name on it,” Nicholas Bequelin, then an Asia researcher at Human Rights Watch, told Britain’s Guardian newspaper in 2009. “It was the organization [that concerned them]; it was across different social groups and across the country. That’s really one of the red lines for the party.”

Mr. Liu was captured by police shortly before the document’s release and confined to a windowless room north of Beijing. His final public statement was in court, days before he was found guilty of “inciting subversion of state power” on Christmas Day 2009.

“I firmly believe that China’s political progress will never stop, and I’m full of optimistic expectations of freedom coming to China in the future, because no force can block the human desire for freedom,” he said in the statement. Titled “I Have No Enemies,” it was later read at his Nobel ceremony.

The statement included extended remarks about his wife, whose love he described as his “most fortunate experience” in 20 years. “Even if I were crushed into powder,” he said, “I would still use my ashes to embrace you.”

Childhood under Mao

Mr. Liu was born in the northeastern city of Changchun on Dec. 28, 1955, and came of age during the worst years of the Cultural Revolution. In Mao Zedong’s bid to reassert his authority and revive revolutionary zeal, intellectuals and alleged dissidents were “reeducated” through forced labor, and millions of urban children were sent out of school and “down to the countryside” to work at farms and rural communities. Thousands of professionals were attacked and killed.

With his father, a professor of Chinese literature, Mr. Liu worked for a time in Inner Mongolia. He returned to Changchun and graduated from Jilin University in 1982, part of the first cohort to return to college after Mao’s death in 1976. He received a master’s degree in Chinese literature at Beijing Normal University in 1984 and earned his doctorate there four years later.

Mr. Liu was married at a labor camp in 1996, although the marriage was not officially recognized for another two years. In 2012, Liu Xia told the Associated Press that she was allowed to visit Mr. Liu in prison once a month but was otherwise permitted to leave her apartment only to buy groceries and see her parents.

A previous marriage, to Tao Li, ended in divorce during Mr. Liu’s first prison sentence. In addition to his wife, survivors include a son from his first marriage, Liu Tao.

Mr. Liu focused increasingly on his writing and poetry in later years, and from 2003 to 2007 served as president of the Independent Chinese PEN Center. Some of his work was translated into English and published in the 2012 collections “No Enemies, No Hatred” and “June Fourth Elegies.”

The latter featured poems that Mr. Liu wrote each year in commemoration of the Tiananmen Square attacks. The writing, he said, was a means of bearing witness to a tragedy that had been excised from the country’s official histories.

He wrote in one poem:

The day

seems more and more distant,

and yet for me it

remains a needle inside my body

remains a crowd of Mothers who’ve lost their children.