Sea lanes before railways

Both Japanese and Chinese troop movements were predominantly maritime because Korea and nearby China lacked railways or roads capable of moving armies at operational speed. Shipping became the only practical way to carry large formations, weapons, and supplies between useful ports. Japan could coordinate this movement through one army and one navy, while China divided responsibility among several provincial armies and fleets. Major Chinese formations were also committed against internal rebellions, so sea transport could not solve the deeper problem of unavailable or fragmented forces.