Born in Chicago and raised in Manhattan, Koenig was the son of Soviet Jewish immigrants whose family had lived in Lithuania.
He studied at the famous Neighborhood Playhouse School of the Theatre in New York, alongside the likes of James Caan, Christopher Lloyd and Dabney Coleman.
His big break came as the capable young Chekov, who would often joke that everything was invented in Russia.
The character was introduced to appeal to younger audiences, with his Beatles/Monkees-style mop-top haircut.
But Star Trek creator Gene Roddenberry’s studio also publicised the role as a response to criticism in Pravda, the main newspaper of the Soviet Communist Party, about the lack of a Russian character. This was a claim Koenig later denied.
The American show, which aired during the Cold War and Space Race between the US and Soviet Union, imagined a future in which nations worked together to explore the galaxy, and Chekov’s Russian heritage fitted that ideal.
Koenig once said that the character’s purpose on the NBC show was to “set out the bones of the plot and let McCoy, Spock and Kirk fill it in”, according to the Hollywood Reporter., external
He was arguably more integral to the movies, being nominated by the Academy of Science Fiction, Fantasy & Horror for his work on The Wrath of Khan (1982) and The Voyage Home (1986).
Koenig’s seventh Star Trek film appearance was a brief one in Generations (1994) – mainly a Next Generation film – and he later voiced President Anton Chekov in the modern series Star Trek: Picard in 2023.
He also wrote an episode of the original show’s animated series spin-off, in 1973, titled The Infinite Vulcan.