Before anything else, we need to clarify something. The last name Kim, 김, is not pronounced with a K, but with a hard G. As in Giggle. When I was in college, I had met someone with his last name spelled as Ghim. It looks weird but it’s actually how you’re supposed to pronounce it.
That aside, the Chinese character for Kim is 金, which is NEVER pronounced as Kim or Ghim, except for in the last name of a person. This character, which means steel, iron, or gold, is read gheum. There is just no correct way of romanizing how this character is actually pronounced—the closest I can think of is “gum” without the u in the middle.
There are so many Kims in Korea that people don’t usually think about these things but before the establishment of Josun Dynasty (1392), people with the last name 金 were probably called something other than Kim. For example, one of the most popular figures in Korean history is a Shilla general Kim Yu-shin (김유신), who played a pivotal role in defeating the rival states Goguryeo (고구려) and Baekje (백제) and unifying the country in the late 7th century.
In all history books, the general is referred to as Kim Yu-shin and by no other name. However, the most likely scenario is that he was actually called Gheum Yu-shin during his time, as the Chinese character is usually pronounced. So, what happened? What caused gheum to turn into ghim, or kim?
The above diagram deserves its own separate blog posting book, but suffice it to say that a lot of political, business, marital, and all sorts of decisions in East Asia are made based on this philosophy, incredibly even today.
According to this Taoist thinking, the universe is made up of 5 elements—tree, fire, earth (soil), iron (gold), and water. Everyone in this world are born with his or her own element based on the day and the time of their birth. As the diagram shows, someone with the tree characteristic will help people of fire characteristic to succeed and someone with earth characteristic will provide similar support to people born with iron (gold) characteristic. (the outer circular grey arrows)
Conversely, people with water characteristic will harm people with fire characteristic. Get it? Water puts out fire? (the inner starry blue arrows)
The one relationship we are concerned with in this story is the blue arrow from the Iron, Gold element to the Tree element.
In 1392, Josun Dynasty was established by a then-national military hero Yi Sung-gye (pronounced Yi sung-gyay, and more on him in a separate blog posting much later.) The last name Yi in Korea is often spelled as “Lee” or even “Rhee” throughout the globe. Yi = Lee = Rhee = 이 = 李.
When you look at the Chinese character for the Josun founder’s last name Yi (李), do you recognize that the top part is the Tree character from the above diagram? And which element (or, who) supposedly harms the Tree? It is none other than gheum, 금, 金.
So, what do you do if you’re Yi Sung-gye’s top advisor? Do you tell the new King to go around and kill all the first-borns? No, you force everyone with the last name Gheum 金 to start pronouncing it as a different, harmless word, namely Ghim or Kim.
So the story goes, but there is a flaw in this theory. Josun Dynasty is sometimes called the Dynasty of Records, according to historians, because of the impeccable records the Court kept throughout its 500 year history. And nowhere in any of the official records is this gheum to ghim (kim) mandate found.
There is another theory that asserts the change in the pronunciation came during the time of Yuan Dynasty’s control over Goryeo (고려) Dynasty during the 13th century. Ethnically of Mongolian origin, the Yuan people pronounced 金 as closer to kim than the traditional Chinese enunciation being closer to keum prior to 12th century. Although this Yuan influence seems more plausible, no doubt the story of Tree - Iron/Gold adverse relationship is much juicier.
I've noticed two Korean name pronunciations which perplexed me when they were Romanized, Woo 유 (pronounced yu) and Lee 이 (pronounced i) aka Yi, Rhee; then I remembered this essay you wrote and it helped me a little bit more. Still not sure why 이 is Romanized to be Lee.