A dedicated socialist, he made political broadcasts for Harold Wilson's Labour Party in Wales and was active in the Campaign for Nuclear Disarmament (CND).
Although born in Wales, Baker spent most of his formative years in England since his parents moved to London in the mid-1930s.
Although he regretted not accepting the part of James Bond himself, Baker was a friend of and outspoken admirer of Sir Sean Connery's work in the role.
At his peak he earned £120,000 for each film he made, at a time when the average house cost just £3,000. He owned a large house in London and a holiday villa in Spain, while his children attended private schools in England.
At the beginning of his career he struggled to break into films, but a few days before his 22nd birthday he was given the role of the bosun in Captain Horatio Hornblower R.N. (1951).
At the beginning of his career he was typecast as villains until Laurence Olivier invited him to play Henry Tudor in Richard III (1955).
At the time of his death he had been planning to play a rapist in a film, with his Zulu (1964) co-star Michael Caine playing a detective.
Awarded a knighthood in Harold Wilson's resignation Honour's List in June 1976. At the time his knighthood was announced, Baker thought he had beaten his lung cancer following surgery in February of that year. However, although the tumour in his lung had been removed, it had spread into his chest and attached itself to his heart. Since no further surgery was possible, he had only a maximum of nine weeks to live anyway. Three weeks after the announcement of his knighthood, Baker was hospitalized in Spain with pneumonia. As he had died without making the journey to be formally knighted at Buckingham Palace, he cannot be referred to as Sir Stanley, but Queen Elizabeth II agreed that his widow Ellen Martin could use the title "Lady Baker".
Baker served in the Royal Army Service Corps from 1946-1948.
Bore a striking resemblance to his contemporary fellow actor, Australian Rod Taylor.
He formed Diamond Films for the making of Zulu (1964). And later Oakhurst Productions.
He had intended to produce Zulu Dawn (1979).
He was a close friend of Richard Burton from childhood until they fell out in 1967.
He was a close friend of his Violent Playground (1958) co-star Gordon Jackson, who attended his memorial service in Ferndale.
He was awarded the freedom of Ferndale, and in a ceremony which he attended in 1970, the local council placed a plaque on the house where he was born.
He was offered the role of James Bond in Dr. No (1962), but turned it down because he was unwilling to commit to a three-picture contract. Baker may have regretted this decision, since a few years later he asked producer Albert R. Broccoli about the possibility of playing a villain in a Bond movie.
He was warned not to address a CND rally prior to the release of Zulu (1964), in case his left-wing political activism hurt the film's performance in the United States.
His breakthrough as an actor came in 1950 in Christopher Fry's anti-war play "A Sleep of Prisoners" alongside Denholm Elliott and Leonard White. The production later toured the United States.
His father lost a leg in an accident in the mine and was thereafter unemployed until the Second World War took men away into the services. His elder brother Freddie, a miner, died of pneumoconiosis early in 1976 after many years of debilitation and sickness.
His wife Ellen and Richard Burton believed Baker's performance in "How Green Was My Valley" (1975) was so good because he was playing his own father.