The Tiananmen pro-democracy movement in 1989 was no doubt Liu Xiaobo's turning point in life. The then 33-year-old visiting scholar at Columbia University rushed back to Beijing to take part in the movement, and along with three other young intellectuals, went on a hunger strike on Tiananmen Square in support of the protesting students. He was also one of the intellectuals who persuaded students to leave the square when soldiers and tanks descended on the night of June 3. Born in 1955 in Changchun , Jilin province , Liu was sent to work in the countryside with other young people and later returned to his birthplace as a worker during the Cultural Revolution. Liu received a PhD in Chinese literature from Beijing Normal University in 1988. He then went to the University of Oslo and the University of Hawaii as a visiting scholar, before arriving at Columbia University in March 1989. He cut short his stint at the American university just two months later to participate in the Tiananmen movement. He was jailed on anti-revolutionary charges after the June 4 crackdown, and although released in early 1991, he was again imprisoned from May 1995 to January 1996. Upon his release, he continued writing essays critical of the government, and in October 1996 he was sentenced to three years in a re-education-through-labour camp on charges of spreading rumours and libel and disturbing public order. Arguably China's most famous dissident abroad, he has served as president of the Independent Chinese PEN Centre since 2003. He continued to be closely watched by state security agents - his phone was constantly monitored and he was often put under house arrest during politically sensitive dates such as anniversaries of the Tiananmen crackdown. On December 8 last year, Liu was detained over his leading role in drafting the manifesto Charter 08 - which calls for the guaranteeing of basic rights, sweeping political reform and rule of law - shortly before it was released. The December 10 publication date coincided with the 60th anniversary of the UN Declaration of Human Rights and International Human Rights Day. He has been kept in detention since, and his wife has seen him only once. He was officially arrested and charged with inciting subversion of state power in June. Beijing police presented his case to prosecutors exactly a year after he was detained, and he was formally indicted three days later. The police alleged that Liu had fabricated rumours to overturn the government. Charter 08, inspired by Czechoslovakia's Charter 77, was initially signed by 303 intellectuals, lawyers and activists. It specifically demanded free elections, an independent judiciary, guaranteeing of human rights, and freedoms of association, assembly, expression and religion. Supporters say more than 10,000 people inside and outside China have since signed the charter. International groups such as Human Rights Watch, Amnesty International, Reporters Without Borders and PEN have repeatedly called for his release, and US President Barack Obama reportedly raised his case when he visited China last month. The European Union and Washington issued formal appeals this month calling for his unconditional release - a move quickly criticised by China. Liu faces a maximum sentence of 15 years if convicted tomorrow.