This seems to be a pretty common misconception so I take the liberty to digress a bit here. As the original Boss factory is near the town where I live, there have been quite a number of newspaper feature articles on the company’s involvement with the Third Reich.
A few key points:
[ul]
[li]Hugo Boss (1885-1948) was a Nazi by conviction (party member since 1931; heard by witnesses to express pro-Nazi sentiments even after 1945)[/li][li]His company was not a designer brand company (it only became one long after his death) but a common or garden clothing manufacturer, then an uniform manufacturer, after WWII a work clothing manufacturer.[/li][li]During the Third Reich the factory manufactured party/Hitler Youth/SA etc. uniforms, both on contract for the party and for sale to party/Hitler Youth members who had to buy their own uniforms. It was not the designer but a manufacturer to the party-approved patterns. (BTW the design of the original party uniforms was that intended for the Imperial German colonial service - the party got a cheap surplus uniform lot after the German colonies were lost. Hence Brownshirts, from the khaki-ish colour.)[/li][li]The company also got state contracts to manufacture Wehrmacht uniforms (Hugo’s party connections won’t have hurt), and employed forced labour during WW II (a page (German language) from a site on forced labour in Metzingen) [/li][/ul]
Presumably, after the company became a designer brand under Hugo Boss’ successors, management considered the word “Boss” to have more marketing punch than “Holy”, the name of the boss at the time (would ambitious people rather buy a Holy suit than a Boss suit? I think not). The unsavoury history wasnt’a consideration yet.