I'm creating the great samurai houses of the feudal period as the great corporations of Kaidan. I'm creating illustrations that has the feel of a corporate ad, showing vessels and equipment as products created by a given Samurai house, the main corporation uses the houses kammon symbol for a logo. Then I list 4 other companies owned by the same house. Not only are they corporations, but just as their feudal counterpart, each maintains it's own security force (private army), and in every way act as they'd done a thousand years ago, just with sci-fi accourterments.
Takeda Corporation, like their famous Sengoku Period forebears is a great military house, and in the current empire are the military industrial complex. This is a wealthy and powerful martial house.
Shimizu Biotech Corporation, is an homage to my mother's family, as both samurai and as physicians, showing an ambulance fighter scaled ship and a colossal hospital ship.
Sagara Corporation are an ocean and heavy industries company specializes is sea ship building, a sea lander oceanographic station, and the Nautilus small fighter, submersible ship on contract with the Colonial Navy (as the Kaidan Star Empire is a part of the Confederation of Independent Colonies of Colonial Space).If you think it's odd to design an llustration that appears as a corporate ad, I think it's a great way to build the setting...
I plan to do five or six more...
Each house will get a page or two of text content, describing it's history and it's direction in the 'modern age', each one will sport a private security force which is their private army, much as what they would have had in the feudal times. Since the largest Japanese Corporations today were the great samurai houses during the Sengoku Period, it only makes sense that in a sci-fi megacorp setting, the megacorps are the great samurai houses.