When Hegel said of Africa in Lectures on the Philosophy of History that it was “no historical part of the World; it has no movement or development to exhibit”, he was lamenting the perceived lack of a European-style Enlightenment on the continent. Today, we know better. The region south of the Sahara, in particular, is rightly regarded as one of the intellectual centres of the world, with the 13th to the 17th centuries an especially fertile period for the production of its celebrated manuscripts.

In English, we principally know the name “Timbuktu” as a stand-in for the idea of something far away and inaccessible. Since 2012, the name has been said for another reason, because in the spring of that year the Tuareg rebel group Ansar Dine, allied with Islamist militants, set about destroying the city’s ancient mausoleums and manuscripts. Just as the more recent destruction of Syria’s ancient buildings in Palmyra by Isis has captured international attention, the losses at Timbuktu are now irrevocably part of the layers of memory around the old city.

The loss of these unique objects (40,000 manuscripts are thought to have been destroyed, along with 16 mausoleums of Sufi saints and scholars) has raised awareness of what we might call “cultural terrorism”, and has produced an unprecedented circumstance in international law. Ahmad al-Faqi al-Mahdi, a Tuareg alleged Islamic militant, has appeared at the International Criminal Court in The Hague, accused of war crimes relating to the destruction of cultural sites. It is the first case of its kind.

At the British Library’s new exhibition about the intellectual heritage of the subregion, “West Africa: Word, Symbol, Song”, the adviser Gus Casely-Hayford tells me that the “war crimes” label is completely accurate. The attitude to ancient manuscripts in places such as Timbuktu is different from that in the west, he explains: they are living documents, meant to be used. An attack on them is an attack on a whole way of life.

“Artefacts like these are the centre of the community, the focus of identity,” he says. “Al-Mahdi wanted it to be known that he is a teacher; a man who understands the significance of destroying these things.”

Marion Wallace, curator of African collections at the British Library, explains that many of the surviving hundreds of thousands of manuscripts – rescued by local “book traffickers” who smuggled them out of harm’s way – are now to be housed in a state-of-the-art research facility. As we examine a loose-leaf “saddlebag” Quran dating from the late 18th or early 19th century, Wallace explains that such manuscripts were never intended to be behind glass, but were designed to be read one page at a time while, say, travelling on a camel.

There is a photograph in the exhibition of an imam sitting on the floor of his sitting room, exhibiting a manuscript for the camera. Around the centuries-old document, you can see a pile of clothes to one side of him, a tray of drinks on the other, the television in the background: the rest of life.

“I can remember being in a library in Timbuktu before 2012,” says Casely-Hayford. “It was poorly lit and there were shafts of light streaming in from the small windows. You could see specks in the light, fragments of manuscript in the very atmosphere.” In this part of the world, erosion is a mark of respect and reverence, rather than regrettable decay.

The exhibition hopes to set this working manuscript culture in the context of West Africa’s intellectual tradition, stressing the continuity from ancient writing through music, storytelling and cloth design. Yet there is tension here, too: although many hundreds of thousands of precious artefacts were saved from destruction, they will likely never be handled in the same way again. Libraries and museums can preserve the past, but they are less good at letting it breathe.

West Africa: Word, Symbol, Song is at the British Library until 16 February, 2016. See www.bl.uk