In the early 17th century during the Tokugawa shogunate (1603–1867), the first "shōgun" Tokugawa Ieyasu intended to subject the kingdom to enable intermediary trade with China, and in 1603 ordered the Ryukyuan king to pay his respect to the shogunate. As the king did not react, with the instruction of the "shōgun", the Satsuma feudal domain of the Shimazu clan in Kyūshū incorporated some of kingdom's territory during the 1609 Invasion of Ryukyu. They nominally let a certain level of autonomy and independence to the kingdom due to Ming's prohibition of trade with the shogunate, but forbade them trade with other countries except China. The Amami Islands became part of Shimazu's territory, taxes were imposed, making them subordinate in the relations between Japan and China. Until the invasion, the Shimazu clan lords for four centuries had a vague title of the "Lords of the Twelve Southern Islands" or "Southern Islands", although initially meaning the near Kyushu islands, then covering all the Ryukyu Islands. Later in the 1870s this was used as a "justification" of Japan's sovereignty. From 1609 the Ryukyuan missions to Edo started which lasted until 1850.