When he saw the letter, Donny George Youkhanna knew it was time to get out of Iraq.

It was late this July, and someone had dropped an envelope containing a bullet on his parents' driveway in Baghdad. The writers threatened to kidnap and behead Mr. George's teenage son, Martin. They knew that the boy's father worked with the Americans, they wrote, and they accused the boy, a Christian like his father, of teasing Muslim girls.

It was too much. Within a few days, Mr. George, 56, an Iraqi born and bred, had sent his family by car to Damascus, Syria. Then he filed for retirement from the Iraq State Board of Antiquities and Heritage, where he was president, and the Iraq Museum, in Baghdad, where he was director general. After that he packed a few suitcases, locked the family apartment, and left.

With that, the country lost its most prominent archaeologist.

Since the U.S.-led invasion of Baghdad, in 2003, Mr. George had made it his business to remind the occupiers that Iraq was the same Fertile Crescent they had read about in schoolbooks. (He was lecturing American troops about ancient Mesopotamia one day at the Baghdad airport when a soldier asked him, "Where's Mesopotamia?") He had made several appearances in the international press to discuss the looting of the Iraq Museum and the efforts to locate and recover the artifacts. Throughout, Mr. George cut the figure of a man minding the cradle of civilization. And then he was gone.

When the envelope with the bullet inside it appeared, Mr. George telephoned Elizabeth C. Stone, a professor of anthropology at the State University of New York at Stony Brook and one of his closest overseas friends and colleagues. He told her what had happened, and they agreed that he had to flee.

The next day, Ms. Stone wrote an e-mail message to Shirley Strum Kenny, president of Stony Brook, asking if the university might be able to offer Mr. George a temporary appointment. "I thought it was like putting a note in a bottle and throwing it out in the ocean," Ms. Stone says.

As it happened, Ms. Kenny went for the idea immediately. "Within a week, we knew that we could bring him here," says Ms. Stone. Later in the summer, $10,000 for Mr. George's one-year appointment arrived from a group called the Scholar Rescue Fund, an organization that tries to find academic safe havens for scholars who have had to flee their countries....

While he was still in Iraq, Mr. George had been frustrated to see the Iraqi State Board of Antiquities and Heritage come under the control of the radical Shiite al-Sadr Party. It seemed to him that the board's new leaders cared much more about the heritage of Islam than the thousands of years of culture that preceded it.

His street in Dora, a predominantly Christian neighborhood in Baghdad, used to have just under 100 families living along it. Now, he had heard, there were only two or three left. A January attack at Al-Mustansiriya University killed 70 people. The employees of the Iraq Museum, in Baghdad, have been telling Mr. George that these days they go to their offices only about once a month — to collect their pay — because the streets are so dangerous.

"There was some time in the Sumerian period that was almost the same," said Mr. George. In his Stony Brook office, overlooking a parking garage and the woods surrounding the campus, he recalled a Sumerian writer who had chronicled that time, some 5,000 years ago.

"His final sentence," said Mr. George,"was, 'We don't know who's the king, who's not the king.'"