Iraqi artifacts that were smuggled into the United States at a ceremony marking their return to Iraq on Wednesday.

WASHINGTON — The line of people snaked around the blue tablecloth, as government officials and archaeology scholars paused to admire the ancient clay tablets and seals lined in rows.

Here, in the backyard of the Iraqi ambassador’s home on Wednesday, was closure for these artifacts: a ceremonial transfer back to Iraq, where they had been looted from archaeological sites. Their coming return there will complete a long, circuitous voyage through Israel and the United Arab Emirates to Hobby Lobby, the arts and crafts chain, and eventually into the hands of the United States government.

The samples carefully lined on the table were just a small fraction of the thousands of smuggled artifacts that Immigration and Customs Enforcement formally returned on Wednesday.

“To have them in my residence is to underline that they’re coming home,” said Fareed Yasseen, the Iraqi ambassador to the United States, speaking after he and Thomas D. Homan, the acting director of ICE, signed the ceremonial transfer. “We really have a sense of kinship to these artifacts.”

The artifacts, which are from the second and third millennium B.C., will eventually be taken to the National Museum of Iraq in Baghdad to be studied and displayed. Several tablets are from the ancient city of Irisagrig and date to between 2100 and 1600 B.C.

Hobby Lobby, which is owned by evangelical Christians known for their interest in the biblical Middle East, originally bought the collection from an unnamed dealer for $1.6 million in December 2010. The purchase, prosecutors later said, was completed despite being “fraught with red flags,” including warnings from an expert on cultural property law hired by the company that the artifacts were possibly taken from archaeological sites in Iraq.

“Stealing a nation’s cultural property and antiquities is one of the oldest forms of organized transnational crime,” said Mr. Homan, who will soon retire from the agency. He said more than 1,200 items had been returned to Iraq…