https://en.wikipedia.org/wiki/Sakhalin#Early_history

The Chinese in the Ming Dynasty knew the island as Kuyi or Kuwu (Chinese: 苦兀; pinyin: Kǔwù), and later (and at present) as Kuye (Chinese: 庫頁; pinyin: Kùyè). There is some evidence that the Ming eunuch admiral Yishiha reached Sakhalin in 1413 during one of his expeditions to the lower Amur, and granted Ming titles to a local chieftain.[6] Under the Ming Dynasty, commerce in Northeast Asia and Sakhalin was placed under the "system for subjugated peoples", or ximin tizhi. These suggest that the island was at least nominally included under the administration of the Nurgan Regional Military Commission which was set up by Yishiha near today's village of Tyr on the Siberian mainland in 1411, and operated until the mid-1430s.[6] A Ming boundary stone still exists on the island.