本文分從貨幣圈、勢力圈、穀物圈及原料圈諸方面，試圖說明1930年代末期，世界船艙載重量的地區分配，集中遠東環太平洋海域，推升了日本商船在世界船艙總載重量所佔之地位，此一變化顯示日、英航運興衰消長的激烈競爭及其特徵。本文首先說明，1930年代末期，當世界經濟重心由大西洋移轉至太平洋之際，英國商船因歐洲戰事的關係，船隻向大西洋方面集結，日本則趁勢在遠東環太平洋海域發展了世界一周航線的遠東航程。本文其次說明，1930年代末期世界海運市場由倫敦轉到紐約之後，英鎊成了弱勢貨幣，但美元尚不足成強勢貨幣，使日圓有可乘之機，轉而有助於日本商船及世界一周航線、跨洲際航線在遠東環太平洋海域的發展。本文最後又說明，戰爭意味穀物圈的沒落及軍需原物料圈需求的成長，大西洋及太平洋諸多交互之小麥航線趨於蕭條之際，1936年後鐵礦、煤炭、鋼鐵等軍需工業原料為中心的海上運輸激增，創造了新的海運市場，可見遠東環太平洋航線激增，影響了英、日商船的興衰消長。本文總結此一新的海洋秩序，並說明日本海運幾獨佔遠東環太平洋海域，對以中國為中心的亞洲所發生的作用及其所反映的意義。

Abstract This article examines the relative decline of British maritime power in the Pacific during the early period of the Second World War. It focuses on questions of currency, power, grains, and raw materials to explain how the concentration of world shipping ship deadweight in the Asia-Pacific sea area raised the level of importance of Japanese ships, specifically in terms of their share of world total deadweight, a change that reflected the fierce competition between Japanese and British shipping interests. This article first analyses how, at the end of the 1930s as the center of the world economy moved from the Atlantic to the Pacific due to the war in Europe, British ships gathered in the Atlantic and the Japanese took the opportunity to establish a round-the-world route in the Far East of the Asia-Pacific sea area. Second, this article also explains how, after the center of the world shipping market moved from London to New York in the late 1930s, the pound sterling weakened even as the US dollar remained a relatively weak currency, which presented an opportunity for the rise of the Japanese yen. These conditions aided the development of Japanese shipping, helping to build round-the-world routes and cross-continental routes in the Asia-Pacific sea area. Third, this article examines how the war led to the decline of the grain trade and the growth of trade in military materials. With many wheat routes in the Atlantic and the Pacific depressed, from 1936 a sharp increase in demand for the ocean shipping of scrap metal, iron ore, coal, steel andother military industry materials created a new shipping market, leading to a rapid increase in Asia-Pacific routes. Under these conditions, Japanese shipping gained the upper hand over British shipping. In sum, a new maritime order was created in which Japanese shipping almost achieved a monopoly in the Asia-Pacific sea area, which had a great influence on China-centered Asia.