Mihri Belli was a prominent leader of the socialist movement in Turkey. He fought for the partisan side in the Greek Civil War. Belli was repeatedly prosecuted and sentenced to prison for his political views, and was altogether imprisoned for 11 years, and forced into exile for another 18. Belli wrote several influential books on the Turkish left and was, for many years, a source of inspiration for leftist Turkish youths.
Belli returned to Turkey in 1940, where he joined the illegal Communist Party of Turkey. Turkey was at the time under a one-party regime. The government, under the influence of the German advances in the initial years of World War II, had abandoned its policy of friendship with the USSR. The only opposition party in Turkey in these days was the underground TKP. Belli, after returning to Turkey, contacted the illegal party via his elementary-school friend David Nea, who was the party secretary for Istanbul at the time. Belli became a member of the central committee of the TKP in 1942. He served as assistant professor with professor Fritz Neumark at the Faculty of Economics of Istanbul University in the years 1943–1944. There he was among the founders and organizers of the İlerici Gençler Birliği. In 1944 he was arrested for these activities and sentenced to two years imprisonment and exile.
Belli left Turkey in 1946, and joined the Greek Civil War as a guerrilla fighter. He rose to the rank of lieutenant-colonel in the Democratic Army of Greece. He was wounded twice in battle, and was treated in Bulgaria and the USSR. In 1950 he was imprisoned in Turkey for a short while for entry without a passport and illegal possession of a handgun. Shortly after his release, he was imprisoned again in 1951 in a wave of TKP arrests. This time he was sentenced to seven years in prison and two years and four months of forced relocation. A documentary about his time in Greece, entitled "Καπετάν Κεμάλ, ο σύντροφος" was made by the prominent Greek filmmaker Fotos Lamprinos.
Turkish revolutionary movement
During the 1960s, Belli could write and speak without having to use an alias. Nevertheless, also in that period he served prison time for various articles and speeches. He was part of the group who published the revolutionary magazines Türk Solu and Aydınlık Sosyalist Dergi. Expelled from the TKP, he joined the newly formed Workers Party of Turkey. At this time, he developed his well-known thesis known as Milli Demokratik Devrim, abbreviated MDD. With his friends, he contacted Deniz Gezmiş and Mahir Çayan, who were at the time leaders of the youth movement amassing popular support. The ideas of MDD quickly gained prominence among the leftist youth movement; it became the main theoretical framework for most of the leftist groups that flourished in Turkey in that period and played a key role in the '68 movement in Turkey, giving it a Marxist and revolutionary characteristic. Mihri Belli left Turkey after the 1971 military coup to avoid arrest, and was for a while a guest of the Palestinian Liberation Organization. He returned to Turkey briefly, en route to Western Europe. There he stayed for a while and helped with the magazine Yurtsever. He was back in Turkey when the centre-left Republican People's Party under Ecevit emerged as the largest party in the 1973 elections. After the amnesty of 1974, he founded the Labour Party of Turkey in 1975. Immediately after the founding of the party, the prosecutor's office of the Martial Law Court took notice and demanded the removal of the wordKurd from the party program and other documents. The Constitutional Court banned the TEP for demanding equal rights for Kurds. In 1979, Belli faced an assassination attempt in which he was severely injured. After the 1980 military coup, he left for the Middle East. From there he moved to Sweden, where he followed the Kurdish movement closely until he returned to Turkey in 1992. In 1997 he met with Abdullah Öcalan, where they came to the common conclusion that a solution to the Kurdish issue under the umbrella of a unitarian state, instead of a federative solution, was possible on the basis of equality and voluntary union. The report of this meeting was later published in book form. In 1996 Belli participated in the founding of the Freedom and Solidarity Party, and that of the Socialist Democracy Party in 2002. He was a candidate for member of parliament for Istanbul in the 2002 elections. In 2005, the portraits Belli had made 50 years earlier, while in prison, were presented in an exhibition "Lines From Prison". Together with several other founding members he resigned from the SDP in 2007 and took part in the 2008 founding of the Workers' Socialist Party, better known by the shortened name Socialist Party, along with others who left.