I seem to recall the shop keeper saying it was designed or mostly worn by the royal and well to do persons in Hyrule. It seems no strech that the armor would have insignias of the royal family and of the Hyrule Kingdom in general, and the suit is only obligatory, therefore, to the time and place in which it was made.

While it is no strech to say that, given that the suit of armor was one of a kind, and it was said to be worn by royalty, it may have been worn by a prince, or even a king. Its original intent and manufacturer, however, remains a mystery, and specifics about who exactly wore it or who made it, cannot be conclusively garnered.