John Gilbert was infatuated with Lillian Gish and would mess up his "love scenes" with her on purpose, so he could keep kissing her.
Although the source of the movie is listed onscreen as "Life in the Latin Quarter", this is a rough translation of the actual French "Scènes de la vie de Bohème" by Henri Murger, which was serialized in "Le Corsair" in 1847-1849.
Star Lillian Gish and costume designer Erté had run-ins over the design of her costumes. She refused to wear a corset he designed and insisted on silk rather than cotton. The designer's refusal to work within Gish's demands are considered to be one reason why his career as a designer in Hollywood did not last long.
A woman is called a "light woman" by a man. This translates to a tart or prostitute.
La Bohème later became the inspiration for the hit Broadway musical RENT.