Yeo U-gil

[2] The diplomatic mission functioned to the advantage of both the Japanese and the Koreans as a channel for maintaining a political foundation for trade.

[3] This delegation was explicitly identified by the Joseon court as a "Reply and Prisoner Repatriation Envoy" (회답겸쇄환사; 回答兼刷還使).

"[4] A diplomatic mission conventionally consisted of three envoys—the main envoy, the vice-envoy, and a document official.

Also included were one or more official writers or recorders who created a detailed account of the mission.

[5] In 1607, Yeo U-gil was the main envoy and Kyŏng Sŏn was the vice-ambassador.