In the pre-Qin period, some tribes in Dongyi lived by the sea, and the living area of the Chinese nation was constantly approaching the sea. According to the Chronicle of Bamboo Slips, Xia Zeng "went east to the sea", that is to say, he took a large group of people to the seaside. As for the purpose of this trip, some people say that the word "hunting" may mean conquering disobedient tribes, while others say that they want to visit the sea for tourism. Anyway, there is no doubt that he wants to meet the sea dragon king at the seaside. The ancestors of merchants had the custom of worshipping Poseidon. People think that shipbuilding and navigation technology have reached a high level. After the destruction of Zhou Wuwang's business, some remaining businessmen crossed the ocean and moved eastward to today's America. Although this statement is still controversial, many scholars at home and abroad have written books and tried to prove it with the discoveries on the American continent today. During the Spring and Autumn Period and the Warring States Period, coastal countries such as Yan, Qi and wuyue all had relatively strong naval forces and fought naval battles for hegemony.