Flag with white and black stickmen

I was watching a videoclip from 1996 from a rodeo-show in the United states. I noticed a flag that some of the persons riding a horses had.

The flag showed three stickmen holding hands. The stickman in the middle had a black color, and the two on the sides had white.
I think I have seen it some where on the internet before, but I cant find any info o this...

I was wondering if anyone could tell me what kind of a sign this is?

There was also a white flag with a blue square in the upper left corner. Can´t seem to find anything about that flag either.