“Nothing can compensate the loss of such heritage,” he said.

The Islamic State has damaged or destroyed scores of historic sites and monuments as part of a nihilistic campaign to eradicate remnants of cultures it considers anathema to its extremist vision of Islam. They have included ancient ruins like Nineveh, Nimrud and the tomb of Jonah in Iraq; Palmyra in Syria; and medieval Islamic sites like the tombs of Yahya ibn al-Qasim and Ibn Hassan Aoun al-Din in Mosul.

St. Elijah’s was near the Mosul airport, on land that during Saddam Hussein’s rule was part of a military base, putting it off limits to most Iraqis for decades. There were 26 rooms in varying states of decay arrayed around a central courtyard. The 11th-century church at the site had a baptistery, nave and altar that were largely intact, though its walls had cracked enough to let in sunlight and rain.