The Yayoi people accumulated wealth through land ownership and the storage of grain, especially rice which became a precious trade commodity.
They also carried on trade all over the country in various other goods, including cloth, silk (which was produced in Kyushu from around 1st century A.D., metals, salt, wooden tools and crafts, stone tools, bronze weapons and bronze bells and other commodities.
Evidence of trade was found in Tohoku (rice brought there); numerous stone reapers (produced at Tateiwa site, Iizuka city, Fukuoka prefecture); stone axes (produced at and distributed from Imayama, Nishi-ku, Fukuoka city); rough unfinished as well as finished wooden tools (produced in the vicinity of Uryudo site, Higashi Osaka City); shell bracelets from south seas found on Yayoi buried skeletons (Tateiwa, Fukuoka prefecture and Yoshinogari, Saga prefecture).
New developments in glass technology and metallurgy also resulted in many new products becoming available for trade. Increased trade within the continent and within Japan. Each district in Yayoi Japan had a marketplace. One trading exchange centre was Asahi in Aichi Prefecture, the largest settlement ever found, covering almost 200 acres (vs. 5-70 acres of the average settlement).
Rice was the most precious food commodity and resource produced by the community but that became controlled by a few elite members within the community. The production of rice led to fixed or permanent settlements and the need to defend their territory as well as to expand boundaries when local populations grew.
This led to increased fighting, in which those few who controlled metal weapons in addition to warrior forces would have the upper hand.
Those who able to control the resources in Yayoi society became members of society with an elite status. They maintained their position and showed off their status by acquiring ceremonial goods that they considered prestigious like bronze mirrors and bronze weapons, the metal raw materials for which were hard to come by, and could only be got from the mainland.
As metal ore resources were scarce in Japan, whoever controlled metal implements became wealthy and would possess high status and ranking in the Yayoi society. Since metal ore came from Korea, only chiefdoms that had strategic allegiances with Korean tribes, gained access to metal resources. The inter-tribal powerplay and warfare led to the formation of numerous small kingdoms or chiefdoms within Yayoi Japan.
Bronze mirrors were prestige goods that were exchanged with other persons with whom kinship ties were forged. The Yayoi period was an age when tribal blood kinship groups were formed and political ties consolidated — and the process, it is thought, involved various rituals connected with the worship of ancestral deities.
According to Chinese documents, Yayoi society had many layers of hierarchy in which people were of different ranks and status. They gave different titles to men of different ranking. Men of high status had four or five wives while lower-rankiing men had only two or three. When lower-ranking persons met a superior on the road, they bowed and stepped aside for their superiors to pass by. At the very bottom rank of society were the slaves. Queen Himiko was said to have been interred along with 1,000 slaves.