I can't say, but it was modelled on British officers' waistcoats.
Well you might be fascinated to know that Britisch officers had knitted waist coasts.  I'm unsure about other sweaters though.
I wear cardigans because I look classy and cultured. Well, cardigans are mostly associated with the Roaring Twenties' college culture. That's cool, do you know when they were first made? I don't know it's origins, but it was popular in the Roaring Twenties and early 30s, as well as the 1950s, 1970s, and 1990s. Interesting, what are they usually made of? I don't have that information here right now, but it's a knitted sweater. What are some other types of knitted sweaters?
It is modelled after the knitted wool waistcoat that British officers supposedly wore during the war.