Sean Gilman’s review published on Letterboxd :
Li Han-hsiang's hunagmei musical adaptation of an oft-told true story, that of the concubine Wang Zhaojun in the later days of the Western Han Dynasty (sometime in the 30s BC). In this version of the story, after refuses to pay a bribe to the royal portrait painter, Mao Yanshou, Wang (played by Linda Lin Dai) languishes in the place unseen by the Emperor for three years. When he finally does meet her, they fall instantly in love. However, due to the treachery of the now-fled Mao, Wang is forced to leave the Han court and marry the nearest Xiongnu chieftain. (This is the correct name for this group of people, though they're called "Huns" in this translation. The Xiongnu, who occupied roughly the same steppe area as the later Mongols, may very well have been related to the Huns, or possibly even the same group, but the history of the nomad horse archers of Central Asia is notoriously slippery.)
Wang is thus portrayed as a heroically patriotic figure, exchanging her love and her beautiful life for the dusty barbarian plains solely for the good of the Empire (her marriage will avert a war between the Han and the Xiongnu). That Li divides his story roughly in half, the first part chronicling the life of a woman literally reduced to a transactional object (the emperor chooses his women by their portrait, and the women must pay the painter to get a favorable image), the second showing how that same woman, rather than seeking revenge, instead sacrifices herself for the sake of that society that so reduced her. But not before she vents her furious anger at the painter who so wronged her, lecturing this cowardly and once-powerful man about the true nature of things, of honor, and of patriotism. She's a superhero, but the fact that she has to be is a tragedy.
The imdb dates this to 1967, citing only the US release date. Letterboxd says 1959, which may be what it says on the DVD case. Both the Hong Kong Movie Database and Hong Kong Cinemagic say 1964, as does Stephen Teo's book Hong Kong Cinema.