His wife, who now lives in Italy, did not respond to repeated attempts to reach her.

“I cut off ties with everyone, as I didn’t want them tracking me down,” he said about family and friends in Romania. “I knew it was hard for my daughter, but I felt it would be better for her.”

After a 7.6-magnitude earthquake struck Turkey in August 1999, resulting in an estimated 17,000 deaths, those in Romania who knew Mr. Constantin wondered if he had been among the dead.

It wasn’t until 2013, after not hearing from her husband for 14 years, that Mr. Constantin’s wife asked a court to declare him dead. With family and friends testifying that they had not heard from him since 1999, and the Turkish Interior Ministry saying they had no record of him for that period, the Romanian court concluded that he was most likely dead.

His death certificate was issued in May 2016, with the year of death listed as 2003, the same year his passport expired.

Mr. Constantin, who was living in Istanbul at the time, was oblivious to all of this. When the authorities detained him, he was told that his case was classified and that he would never be allowed to return to Turkey. It was only upon landing in the Romanian capital after 26 days in Turkish detention that he was told he was legally dead.

“At the airport in Bucharest, I was surrounded by customs officials. They said, ‘You’re dead,’” he recalled with disbelief. “I thought they were joking. I was the only one who didn’t know. The people who escorted me off the plane knew, everyone knew except me.”

For the next six hours, he was questioned about his hometown — where the schools and factories were, details about his family, including dates of birth. Finally, he was released.