Corea

All China was formerly divided by the Chineſe Emperour Xunus into 12 Provinces; afterwards the Emperour Yua, who took upon him the Government after the death of Xunus, about 260 years before the Incarnation of our Saviour, reduced all China into Nine Provinces, which only at that time comprehended the Northern Parts of China, and had for their Confines the River Kiang. But after that they had Conquered the Southern parts by degrees, and had ſomewhat civilized the Inhabitants, the whole Kingdom of China was divided into 15 Provinces : Amongſt theſe alſo they reckon the Province of Leaotung, which is ſituated on the Weſt of Peking, where the great Wall begins, and the Hanging Iſland of Corea; both which pay Tribute to the Emperour.

1669 [1665], John Nievhoff, translated by John Ogilby, An Embassy from the Eaſt-India Company of the United Provinces, to the Grand Tartar Cham Emperour of China, London: John Macock, translation of original in Dutch, →OCLC, page 6

I would take the ſame method if I was to go to diſcover the North Eaſt Paſſage. I would winter about Japan, Corea, or the North Eaſt part of China; and taking the Spring and Summer before me, I would make my firſt trial on the Coaſt of Tartary [...]

1699, William Dampier, A New Voyage round the World, page 274

The Mantchews, thus maſters of Corea, endeavoured to compel their new ſubjects to ſhave their heads, after their manner, and to adopt the Tartar dreſs.

1788, Jean-Baptiste Grosier, translated by unknown, A General Description of China, page 245

In the latter country it is mostly black and known as Whitby jet, while in Corea and Japan it is red in color and opaque.

1922, Elizabeth F. Parker, Amber, page 12