Alright, this is an argument settler.....
 

Where does modern stencil art stem from?

um, my guess would be ancient stencil art?

I heard somewhere that it was the Aboriginals. (I'm usually wrong though)

What do I win? :D

It's just that a friend of mine told me modern stencil art stemmed from hip hop,
and I told him art can stem from anywhere as much as it can stem from hip hop, as much as it can stem from anywhere.

I can tell you Hip Hop dance moves, stem from Northern Soul.

(just thought I'd get that in).

What exactly is modern stencil art?

Good question.

Banksy.

I am soooo suprised his name didn't come up in the first response! haha.

Some questions just are not meant to be answered without enough time given to explain them.