The character of Prince George (Michael York) has been said to represent King Charles III. Time Out said that the character was "obviously Charles, though called George."
The film was very popular in Myanmar, where Michael York was mobbed by fans.
Director Lewis Gilbert previously directed You Only Live Twice (1967) which was also set (partially) in Japan.
Second of two cinema movie collaborations of director Lewis Gilbert and French cinematographer Henri Decaë. The first had been Operation Daybreak (1975) about two years earlier in 1975.