However, one of the reasons why Yuan Dynasty wanted to invade Japan was to gain the economic advantage; therefore, Yuan Dynasty was eager to establish the economic ties with Japan and Japan also had a strong desire to maintain the economic ties with the Chinese continent established by the trade between Japan and Sung Dynasty in China.
だが、元の日本侵略の要因として経済的な利権を求めたことが挙げられるように、元側に日本との経済的関係を望む意向が強く、反対に日本側も日宋貿易によって確立された中国大陸との経済的関係の維持を望む意向が強かった。