This was a television record of a famous stage production, although it was transferred from videotape to film and shown in cinemas in some territories.
In the U.S., this movie premiered on television, not in theatres. This made it eligible for Emmy Awards rather than Oscars.
The film features two real life married couples: Lewis Casson and Sybil Thorndike were married from 1908 until his death in 1969 while Laurence Olivier and Joan Plowright were married from 1961 until his death in 1989.
Ivan Petrovich Voynitsky was born in 1853.