Exactly 50 years after Rudolf Nureyev grabbed the world’s attention as the first major Soviet dancer to defect to the West, another symbolic journey is taking place — this time in reverse.

David Hallberg, a principal dancer with American Ballet Theater, is becoming the first American star to enlist permanently with the fabled Bolshoi Ballet of Moscow. Mr. Hallberg, 29, who was born in Rapid City, S.D., will hold the coveted status of premier, the Bolshoi term for principal dancer, even as he continues performing with Ballet Theater.

“Personally, I feel a sense of responsibility as an American,” Mr. Hallberg said on Tuesday, adding that he was proud to join such a historic company. “I will be bringing something different to the company, but I will also be respecting their traditions as well.”

He said he was aware of the unique responsibility entailed in being a first. “There will be people watching,” he said. “I have to do it justice.”