In [[1436]], Sadamori received a monopoly (within Japan) on trade with Korea. In [[1443]], he secured an arrangement with the Korean royal court under which all Japanese traveling to Korea required a (Korean) travel permit issued by the Sô house. This strengthened the position or authority of the Sô, preventing others from competing with the Sô for prominence,<ref>Robinson, 53.</ref> and represents a significant development in setting a foundation for Sô power, and the Sô-Korea relationship, for centuries afterward. | In [[1436]], Sadamori received a monopoly (within Japan) on trade with Korea. In [[1443]], he secured an arrangement with the Korean royal court under which all Japanese traveling to Korea required a (Korean) travel permit issued by the Sô house. This strengthened the position or authority of the Sô, preventing others from competing with the Sô for prominence,<ref>Robinson, 53.</ref> and represents a significant development in setting a foundation for Sô power, and the Sô-Korea relationship, for centuries afterward. |