What Russian born author started as a screen writer before turning to novels?

Boris Vasilyev started as a screenwriter, but soon began writing novels. He served in the Russian Imperial Army during the second world war, and was born into aristocracy, even though the aristocrats didn’t really hold a lot of power when he was born in 1924. (The Wikipedia page says he fought in World War I, but that’s not possible, so disregard that if you chose to look up more information on him).

One of his most famous pieces is called “Don’t Shoot the White Swans”, and was an environmental protection piece published in 1973. The odd thing about its fame is that it was published and famous in the Soviet Union, Communist China, and other countries of the time that embraced communism.