The Surprise of a Knight

The Surprise of a Knight is a gay, hardcore pornographic film from the United States. Probably released in 1929, it is notable for being the earliest known American pornographic film to depict exclusively homosexual intercourse.

Hardcore pornographic films at the time, also called stag films first appeared in Europe in 1908. By 1920, the first hardcore homosexual sex acts were depicted in the film Le mnage moderne du Madame Butterfly.However, like most of the films which came after it, Le mnage moderne du Madame Butterfly only shows malemale sex acts as deviant, firmly establishes the heterosexuality of the characters, and usually depicts gay sex acts as essentially bisexual e.g., malemale sexual contact occurs while the men are also having heterosexual intercourse. ........

Source: Wikipedia