Marcos Ana, born Fernando Macarro Castillo, was a celebrated poet, lifelong Communist, and perhaps best known as the man who spent the most time imprisoned by the fascist regime of Spanish dictator Francisco Franco regime. Jailed by Franco at the age of 19, he was released 23 years later, in 1961, thanks to an international solidarity campaign led by the likes of Pablo Neruda.

"I am a child of solidarity. It’s not just a beautiful word; it’s an attitude towards injustice, which is still necessary. I owe it my liberty and my life," said Ana.

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Born to a humble family in Salamanca, Spain in 1920, he left school at 13 to work to support his family and soon joined the young Socialists of Spain rising to become a regional secretary just before the outbreak of the Spanish Civil War in 1936. During the war, he joined the Communist Party of Spain and played a key role in the opposition to Franco.

Captured by Franco's forces in 1939, he would spend the next 23 years in jail, surviving two death sentences, torture, and multiple beatings. While in prison, Ana continued his political work. Along with fellow Communists, anarchists and artists he created a clandestine newspaper and offered tutorials to fellow inmates.

It was in prison that he also began writing poems under the pseudonym Marcos Ana, named after his father who was killed by Franco's forces in 1937 as well as his mother who died while he was in prison. The poems, smuggled out by prison guards and comrades who had memorized the lines before being released, were eventually compiled and sent to a printer in Brazil. The publication in Brazil of his first volume of poetry, "Poems From Prison," brought him to the attention of Pablo Neruda, who would go on to spearhead the international campaign for Ana´s release, along with the newly-formed Amnesty International.

After his release in 1961, Ana continued his activism in exile in France as head of the Center for Information and Solidarity with Spain which included Pablo Picasso as an honorary president. From France as a member of the central committee of Spain's Communist Party, Ana toured the world organizing aid and solidarity campaigns for fellow exiles and opponents of Franco.

In a speech in London in 1962, Ana said, "The only revenge to which I aspire is to see the triumph of the noble ideals of freedom and social justice, for which we have fought and for which thousands of Spanish democrats lost their freedom or their lives."

He returned to Spain in 1976 after the death of Franco and ran unsuccessfully as a candidate for the Community Party in the 1977 elections.

During his birthdays, he would subtract the 23 years he spent in jail from his age and often remarked that he felt he had been born twice, first on the day of his birth and later when he was finally released from prison on Nov. 17, 1961. In 2007 he published his memoirs "Tell Me What a Tree Looks Like: Memories of Prison and Life," with a foreword by Nobel Prize winner José Saramago, and to which Spanish filmmaker Pedro Almodovar acquired the film rights in 2008.