User blog comment:Batran99/New Logo for 2017 Contest/@comment-24914438-20170110141837/@comment-5590986-20170113163447

It's based off of a German officer cap (or American)

it became popular when people use it for their mapperball icons.

I think this was the original: http://www.thehistorybunker.co.uk/acatalog/yellowcap500.jpg