According to Wikipedia, the common Korean surname Kim is the same as the common Chinese surname Jin.This is confirmed by another site:http://www.ziplink.net/~rey/ch/queries/messages/9731.html This genealogical site goes into it in detail: http://www.ancestry.com/learn/facts/Fact.aspx?fid=10&yr=0&ln=Kim Kim Korean: there is one Chinese character for the surname Kim. Kim is the most common Korean surname, comprising about 20 percent of the Korean population. According to some sources, there are over 600 different Kim clans, but only about 100 have been documented. Kims can be found in virtually every part of Korea. The two largest Kim clans, the Kim family of Kimhae and the Kim family of Kyongju, are descended from semi-mythological characters who lived two thousand years ago. According to legend, the Kimhae Kim family founder, Kim Suro, came in answer to a prayer offered by the nine elders of the ancient Karak Kingdom. In 42 ad, these elders met together to pray for a king. In answer to their prayer, they were sent a golden box containing six golden eggs. From the first egg emerged King Su-ro, Karak’s first king. The other five eggs became the five kings of Karak’s neighboring kingdom, Kaya. The founder of the Kim family of Kyongju, Kim Al-ji, had similar origins. In 65 ad the king of Shilla, T’alhae, heard a strange sound from a forest near the Shilla capital, Kyongju. On investigation he found a crowing white rooster standing next to a golden egg. From this egg emerged Al-ji, founder of the Kyongju Kim family and subsequent king of the Shilla Kingdom. Because Al-ji emerged from a golden egg, King T’alhae bestowed upon the child the surname Kim, which means ‘gold’. It is estimated that about half of the one hundred or so Kim clans of modern Korea are descended from the Kyongju Kim clan. ======== Som the Kimhaes are descendants of the Kims, not the progenitors. ++++++++++++++++++++ The surname Kang also seems to have Chinese origins according to this site: http://www.yutopian.net/names/10/10kang75.html The 75th most common last name. Descendents of the brother of Zhou Wu Wang, Wei Kangshu. His last name was Ji, and he was awarded the duke of Wei (Qi in Henan). Since his kingdom was within the territory of the previous Shang Dynasty, Kangshu was given the duty of governing the seven tribes of the Yin family (descendents of the royal family of the Shang Dynasty). Since he did a good job, the king made him a big judge in his administration. After his death, some of his descendents were given the last name of Kang to commemorate him. Kangshu's oldest son bore the last name Kang. (Kang means health). Hometown: Sixty miles south east of Runan in Henan Province. This site: http://www.ziplink.net/~rey/ch/queries/messages/6486.html also sheds some light on the origin of Kang: "Kang" means river in Korean and also in Hokkien (Chinese dialect). They sound nearly identical in both languages - pronounced more like "kung". The linguists and anthropologists should figure out if there is a connection in the two "tribes". Coincidently, It is also a surname in name in both languages. I'm not sure if "Kang" means the same thing in Vietnamese and whether or not it is Vietnamese surname.

Surname Kim is not only from Kimhae. Kimhae is a clan of Kim's.