For decades, he was the bespectacled caretaker of some of Syria’s greatest archaeological treasures. He explored the sprawling ruins in his home town, named a daughter Zenobia after its ancient queen, and became so intertwined with its development that one historian called him “Mr Palmyra”.

Now, months after his home fell to the jihadis of Islamic State, Khalid al-Asaad, the retired chief of antiquities for Palmyra, has fallen, too. After detaining him for weeks, the jihadis dragged him on Tuesday to a public square where a masked swordsman cut off his head in front of a crowd, Asaad's relatives said.

His blood-soaked body was then suspended with red twine by its wrists from a traffic light, his head resting on the ground between his feet, his glasses still on, according to a photo distributed on social media by Islamic State supporters.

Before his death, the jihadis had interrogated him in vain about where to find the city’s hidden treasures, Syrian state news media reported, suggesting that the elderly caretaker may have died protecting the same history he had dedicated his life to exploring.

The public killing of Asaad, who had retired a decade before and had recently turned 83, his son said, highlighted Islamic State's brutality as it seeks to replace the government of President Bashar al-Assad with a punishing interpretation of Islam across its self-declared caliphate in parts of Syria and Iraq.

Scholars who knew Asaad said he was less a pure academic than a self-taught scholar passionate about his home town's history. Yasser Tabbaa, a specialist on Islamic art and architecture in Syria and Iraq who lives in Ann Arbor, Michigan, said Asaad was well known in the field as a man who had taught himself to read the city's ancient inscriptions and often presented in English at academic conferences about his decades researching the site.

“He was a very important authority on possibly the most important archaeological site in Syria,” Tabbaa said. Like many Syrian professionals, Asaad was a member of the ruling Ba’ath Party. That surely helped him land the job he would define over decades, but his intimate knowledge of the site made him indispensable to foreign researchers.

"Anyone who wanted to do anything in Palmyra had to work though Khalid al-Asaad," said Amr al-Azm, a Syrian professor of Middle Eastern history and anthropology at Shawnee State University in Ohio. "He was Mr Palmyra."

Asaad was born in Palmyra and spent his life there, leaving only to study in the Syrian capital, Damascus, where he received degrees in history and education, according to the Syrian state news agency, Sana. He was appointed director of antiquities for Palmyra in 1963 as well as the director of its museum, positions he held until his retirement in 2003.

Reflecting how he often managed Palmyra's history like a family business, he passed his two positions to his son Walid. The city's extensive ruins mark the site of an ancient oasis town in the desert northeast of Damascus, and include a theatre, a number of temples, living quarters and cemeteries. Unesco, which named Palmyra a World Heritage site, called it "the consummate example of an ancient urbanised complex."

Many of its main discoveries were made during Asaad's tenure. "Here is where he dedicated his life, revealing Palmyra's precious history and interpreting it so that we could learn from this great city that was a crossroads of the ancient world," Irina Bokova, Unesco's director general, said in a statement on Wednesday, adding that she was "saddened and outraged" by the killing.

The city’s history made it a prime tourist attraction before the uprising against Assad broke out in 2011, leading to the current civil war. As armed rebels took territory elsewhere in the country, Palmyra remained in government hands until May of this year, when the jihadis of Islamic State, also known as Isis, seized it, raising fears that they would destroy some of its rich antiquities and sell others to finance their operations.

Reached by phone on Wednesday in the Syrian city of Homs, Asaad’s son Mohammed said his father had refused to leave the city, thinking the jihadis would not bother with someone his age. “He was a retired government employee and an old man,” Mohammed Asaad said. “He was innocent, so he never thought Isis would hurt him.”

A nephew of Asaad’s, who goes by the name Khalid al-Homsi and used to be his next-door neighbor, said the jihadis arrested his uncle for a few days when they first entered the city but then let him go, arresting him again months later. He said his uncle had supported the Assad government in Syria and had been alarmed when protesters took up arms against the government, but that he had never considered fleeing the city.

“He was very connected to his city and to the antiquities, and he was old,” Homsi said. “Where would he want to go at that age? He said that whatever was going to happen to the people would happen to him.”

As it has seized territory in Syria and Iraq, Islamic State has destroyed a number of historic sites, detonating tombs and destroying statues that are forbidden by its strict interpretation of Islam. In the photo of Asaad's dead body, red writing on a white placard suspended from his waist calls him an "apostate" and lists his alleged crimes, including representing Syria at "infidel conferences", serving as "the director of idolatry" in Palmyra, visiting Iran and communicating with a brother in the Syrian security services.

Before the jihadis entered the city, museum workers moved many of its most precious artifacts to safer parts of the country. Some larger pieces left behind have been destroyed, as have a number of tombs in the area. The jihadis are not believed to have significantly damaged the city’s ruins, and some think they are using them for protection, assuming that the US-led military coalition that is bombing the Islamic State in Iraq and Syria will not bomb a Unesco heritage site.

New York Times