In 1984 the PKK initiated a campaign of armed conflict comprising attacks against government forces in Turkey in order to create an independent Kurdish state. PKK also used force against competing Kurdish groups.
PKK soon acquired a reputation as an effective force for Kurdish rights, and also for social justice within the Kurdish communities. Its violent methods have caused United States, European Union, NATO, Syria, Australia, Turkey, and some others to include the PKK on their lists of terrorist organizations.
Until 1998 Öcalan was based in Syria. As the situation deteriorated in Turkey, the Turkish government openly threatened Syria over its support for the PKK. As a result of this, the Syrian government forced Öcalan to leave the country, but did not turn him over to the Turkish authorities.
Öcalan went to Russia first and from there moved to various countries, including Italy and Greece. In 1998 the Turkish government requested the extradition of Öcalan from Italy. He was at that time defended by the high-profile German attorney, Britta Böhler who argued that he fought a legitimate struggle against the oppression of his people. He was captured in Kenya on February 15, 1999, while being transferred from the Greek embassy to Nairobi international airport, in an operation by the Turkish National Intelligence Agency (MIT). American officials admitted that US intelligence and diplomatic efforts aided in Ocalan's eventual capture. He was then flown back to Turkey for trial. His capture led thousands of protesting Kurds to seize Greek embassies around the world.
Since his capture Öcalan has been held under solitary confinement as the only prisoner on the İmralı Island in the Turkish Sea of Marmara. Despite the fact that all other prisoners formerly at İmralı were transferred to other prisons, there are still over 1000 Turkish military personnel stationed there guarding him. He was sentenced to death, but this sentence was commuted to life-long aggravated imprisonment when the death penalty was abolished in Turkey in August 2002. No one has been executed in Turkey since 1984. The Kurdish Human Rights Project (KHRP) aided this case's decision.
The decision not to proceed with the death sentence was met by protests by Turkish nationalist groups. Kurdish activists regard him as their leader, a political prisoner and even a man of peace. In 2007, lawyers acting for Öcalan, claimed to have produced results from laboratory tests on his hair which appeared to show high levels of toxic metals. The Turkish government has sent a medical team to the imprisoned Kurdish separatist leader amid these claims and the tests found no indication of toxins or abnormalities. A ministry statement suggested the lawyers were trying to revive international interest in their client after the Council of Europe ruled the previous month that the rebel leader was not entitled to a retrial. At 6. March 2008 the Committee for the Prevention of Torture declared that they didn´t find any proof for an intoxication of Abdullah Öcalan.
Since his incarceration he has significantly changed his ideology, reading Western social theorists like Murray Bookchin, Immanuel Wallerstein, Fernand Braudel, fashioned his ideal society as "Democratic Confederalism" and refers to Friedrich Nietzsche as "a prophet". He also wrote books and articles on the history of pre-capitalist Mesopotamia and Abrahamic religions.
In 2008, prosecutors investigating on the nationalist Ergenekon network, accused of terrorism and of conspiracy to destabilize the nation, were interested in Öcalan's contacts while in prison. Öcalan himself asked to be heard as a witness in this case. A retired intelligence officer, Bülent Orakoğlu, went so far as to accuse him of membership in the network.