Japanese Clans as Primary Social Unit
In structure, each [Japanese] clan consisted of a central, dominating house or family, which gave the clan its name, and various affiliated units known as tomo or be. Other categories of subjects also appear, confusedly, in the records, between those two classes of clansmen and the serfs or slaves known as jakko at the very bottom of the ladder (who bore no family name). All were subject to the power of a headman (uji-no-osa), who was the absolute and undisputed leader and master of the clan….
The clan, as a primary social unit, had achieved self-sufficiency through the cultivation of its own rice paddies and the production of its own artifacts, textiles, agricultural instruments, and, naturally, weapons. From the very beginning, the history of these clans was not one of peaceful coexistence. The archaic weapons found in the mounds and dolmens of the period from 250 [B.C.E.] to 560 [C.E.] indicate that, as was true during every other national age of formation, warfare was the predominant condition….
— Secrets of the Samurai, pp. 39-40
