One afternoon in March, I walked through Timbuktu’s Ahmed Baba Institute of Higher Studies and Islamic Research, stepping around shards of broken glass. Until last year, the modern concrete building with its Moorish-inspired screens and light-filled courtyard was a haven for scholars drawn by the city’s unparalleled collection of medieval manuscripts. Timbuktu was once the center of a vibrant trans-Saharan network, where traders swapped not only slaves, salt, gold, and silk, but also manuscripts—scientific, artistic, and religious masterworks written in striking calligraphy on crinkly linen-based paper. Passed down through generations of Timbuktu’s ancient families, they offer a tantalizing history of a moderate Islam, in which scholars argued for women’s rights and welcomed Christians and Jews. Ahmed Baba owned a number of Korans and prayer books decorated with intricate blue and gold-leaf geometric designs, but its collections also included secular works of astronomy, medicine, and poetry.

This vision of a philosophical, scientific Islam means little to the Al Qaeda–linked Islamist group Ansar Dine, which for most of last year ruled Timbuktu through terror, cutting off the hands of thieves, flogging women judged to be dressed immodestly, and destroying centuries-old tombs of local saints. In the summer, the militants commandeered Ahmed Baba, using it as a headquarters and barracks. Then, in January, French forces closed in on Timbuktu. As the Islamists fled, they trashed the library, burning as many of the manuscripts as they could find. The mayor of Timbuktu, Hallé Ousmani Cissé, told The Guardian that all of Ahmed Baba’s texts had been lost. “It’s true,” he said. “They have burned the manuscripts.”

When I visited Ahmed Baba two months later, the rows of wooden bookcases in the large, sunlit rooms were empty. The only traces of the ancient documents were a pile of mottled gray-and-black ashes, a few empty leather cases, and a single book-sized manuscript lying loose on the floor. I picked it up: The spidery Arabic on its cover was mostly obscured by singe marks, the pages inside reduced to dust.

Asking around about the manuscripts’ destruction, however, I heard different rumors. Find Abdel Kader Haidara, people told me. He could tell you more about what happened. So, in Bamako, Mali’s capital 400 miles to the south, I visited Haidara, an unassuming man with a shy smile, a neatly groomed mustache, and a healthy paunch under the flowing robes traditional to Malian men. Sitting cross-legged on the floor of the modest apartment where he now lives, Haidara told me the improbable story of what actually happened to Timbuktu’s manuscripts. “It was only a matter of time before the Islamists found them,” he said matter-of-factly, passing dark worry beads between his fingers. “I had to get them out.”

When Abdel Kader Haidara was 17 years old, he took a vow. Among the families of Timbuktu with manuscript collections (and the Haidaras had one of the largest), it’s traditional for one family member from each generation to swear publicly that he will protect the library for as long as he lives. The families revere their manuscripts, even honoring them once a year through a holiday called Maouloud, on which imams and family elders perform a reading from the ancient prayer books to mark the birth of the Prophet Mohammed. “Those manuscripts were my father’s life,” Haidara told me. “They became my life as well.”