Aurel Stein, with his dog Dash, poses in the desert during his second expedition into China. He returned with what is now acknowledged as the world's oldest printed book, the Diamond Sutra of 868AD.
Aurel Stein, with his dog Dash, poses in the desert during his second expedition into China. He returned with what is now acknowledged as the world's oldest printed book, the Diamond Sutra of 868AD. Photo: British Library
The letter could have been written this morning. Its remorse and embarrassment are as palpable as a thumping headache.
"Yesterday, having drunk too much, I was so intoxicated as to pass all bounds. But none of the rude and coarse language I used was uttered in a conscious state..."
But at least a thousand grape harvests have passed since the words were composed – and sealed in a cave in the Gobi Desert. We don't know who penned the letter, but we do know who found it.
Aurel Stein takes tea in Lahore in the 1890s.
Aurel Stein takes tea in Lahore in the 1890s. Controversy, in the form of objects taken from China, would come later. Photo: Library Hungarian Academy of Sci
And we know where the letter is today. Its emergence is the result of a remarkable but controversial figure, the explorer Aurel Stein, born 150 years ago today.

The haul included the earliest known map of the heavens, a receipt for the sale of a slave girl, medical treatments and Buddhist texts. The greatest jewel was the world's oldest printed book, the Diamond Sutra of AD868.
The apology letter, and other model etiquette missives redolent of Miss Manners, was among thousands of documents Stein obtained from a cave near Dunhuang, China, in 1907.
The find saw Stein hailed in the West, then forgotten. Unlike or Howard Carter or Heinrich Schliemann, Stein's name hardly registers today. Yet the results of his trailblazing journeys have transformed our understanding of ancient central Asia, a region of growing global importance.
For decades Stein has sat in the West's too-hard basket, an uncomfortable reminder of the twilight years of the Great Game, when rival powers viewed the treasures in other people's backyards as theirs for the taking.
In China, though, Stein has not been forgotten. He is viewed as the worst foreign devil to travel the Silk Road. Of all the antiquities the British-Hungarian explorer collected during his forays into China's remote west, it is the Dunhuang scrolls that have ignited the most consternation.
Long after Stein was buried in Kabul in the 1940s, the Chinese people continue to "gnash their teeth in bitter hatred" over his actions, according to one China scholar.
Visitors escorted around the magnificent murals within the cave complex at Dunhuang – now a major tourist attraction – are left in no doubt that Stein is still considered a looter and robber.
Yet, on the eve of Stein's 150th anniversary, it is worth asking what the fate of one of the world's great literary finds might otherwise have been?
Stein bought the scrolls in 1907 from a guardian monk, Wang Yuanlu, who uncovered them within a sealed cave in 1900 where they had been perfectly preserved in the dry desert air for a thousand years. Wang had already parted with a few scrolls to curry favour with local officials when Stein arrived.
Stein feared the remainder would be destroyed or lost to scholarship forever unless he "rescued" them. His fears were convenient, certainly, for a man on a mission funded by the British Museum and the Indian government. And he knew he had a bargain, paying just £130 for his haul.
Yet when the cave was discovered, China had little interest in the contents of this hidden library. When the monk attempted to interest authorities in his find, he was simply ordered to reseal the cave.
Eventually alerted to the cave's importance, Chinese authorities ordered the transfer of what remained to the Beijing. Some items were pilfered along the way. And Wang didn't send everything to Beijing. He kept enough to sell to other visitors. The fate of these scrolls is unknown.
Stein's scrolls are now in the British Library, many have been digitised and can be viewed online.
China may one day ask for them back. But unlike the Elgin Marbles or Rosetta Stone, the Stein scrolls are mostly too fragile for permanent display. So arguments about where they should reside boil down to whether they should be kept in a cabinet in London or Beijing.
The more important point is that today they have been catalogued, are being been studied and are available.
Cultural values have changed since Stein loaded his camels with Silk Road treasures. Today it is shocking to think of him – or anyone – digging, chipping and bargaining their way around desert oases in a quest for antiquities to fill museums. We can't rewind the clock.
But we can acknowledge that the scrolls Aurel Stein acquired from the hidden cave library continue to add to human understanding. And that requires no morning-after apology.
Joyce Morgan is a journalist and co-author of Journeys on the Silk Road. Tap here to buy the ebook.