A South Sudanese man who spent his late teenage and early adulthood years in Philadelphia was freed from prison Saturday, roughly a year and a half after the outspoken activist was arrested in his home country.

Peter Biar Ajak was released after the country’s president pardoned the prominent economist Thursday along with 30 other prisoners. According to Reuters, South Sudan President Salva Kiir said the action was a goodwill gesture to rejuvenate the country’s stalled peace process.

Ajak, now in his mid-30s, is considered one of the foremost scholars and speakers on South Sudan and had been publicly critical of the way the African country approached peace talks to end the civil war that broke out in 2013. That war, which began after a political disagreement between Kiir and his former Vice President Riek Machar, has killed around 383,000 people, according to some estimates.

As war dragged on, Ajak called for a new, peaceful generation of young leaders to rise and run South Sudan — a country that was born only in 2011 after it gained independence from the Republic of Sudan, which itself had suffered from decades of civil war. Ajak was arrested by national security forces in the summer of 2018 as he boarded a plane in Juba, South Sudan’s capital, to attend a youth conference.

Days later, Ajak faced treason charges, which were eventually dropped. He was later sentenced to two years in prison in 2019 after being accused of inciting an uprising behind bars.

Yet decades before Ajak’s arrest drew international headlines, and years before Ajak became a prominent peace activist, he was one of 4,000 “Lost Boys” who came to the United States seeking peace and education after Sudan was ravaged by a brutal civil war. Ajak was 16 when he stepped off a plane in Philadelphia, carrying only a manila envelope containing a chest X-ray that proved he did not carry tuberculosis and immigration papers declaring him a refugee who was permitted to live and work in the United States.

Ajak was assigned to live in South Philadelphia, not far from the Italian Market. He enrolled at Horace Furness High School, and later Central High School, where he graduated as an honor-roll student in 2003. He then went on to study at La Salle University for his undergraduate studies and earned a master’s in international relations at Harvard. Ajak was a PhD candidate at the University of Cambridge when he was detained.

He is married with two children, according to Dale Long, the resettlement volunteer who housed Ajak in South Philadelphia.

In a statement released Saturday by his pro bono counsel, Ajak said: "So many people I know, and countless others at home and around the world have raised their voices and supported me and my family for the last year and a half."

“Words cannot express how grateful I am for their support,” he continued. "... It’s a new year and a new decade, and my wish is that this year will be the start of lasting peace in South Sudan.”

Ajak also told reporters, according to the Associated Press, that his detention had been “extremely harsh” but improved before the release. He said a medical checkup was a priority. A statement from his attorneys said he is resting at home, soon to be reunited with his family.

“His detention was a travesty of justice,” said Jared Genser, one member of Ajak’s pro bono counsel. “I urge the government to engage with the people of South Sudan and to listen and adopt their best ideas, rather than attempt to intimidate or silence those with which it disagrees.”

Ajak’s imprisonment was condemned by numerous prominent local individuals and organizations, including U.S. Sen. Bob Casey (D., Pa.) and Democratic presidential candidate and U.S. Sen. Cory Booker (D., N.J.) — and his detention underscored the problems that remain as South Sudan continues to try to work toward peace. Kiir and Machar signed a peace deal in 2018 under pressure from international organizations and countries, and agreed to form a unity government by November 2019.

That target date was extended 100 days after the deadline was missed. At the time, the U.S. said it was “gravely disappointed” that both leaders had failed to form a unity government in time.

As for Ajak, the Associated Press reported that he said that he will return to his work to ensure peace goes forward.

“Peter is unafraid,” Long, 67, said. “He’s always been brave — too brave for his own good.”