Actually, that's not quite right. (Hooray!!! A topic that I actually know a little something about!!!)
The first poster that said "Gumdo and Kumdo and Kendo are all spelled the same way in Chinese characters" was absolutely correct. Metallurgy, swordsmaking, and swordsmanship started in China, then moved to Korea, then to Japan. In Japan, significant improvements and refinements were made, which then through war and trade, came back into Korea, then into China again. In early Korean history (Paekche, Shilla, around 500 AD), up into the mid Choson Dynasty (late 1400's Korea made it's own alphabet), the Korean elite and the royal court used Chinese characters for literature. The Chinese character for 'Jian Dao' was spoken in Korean as 'Kumdo' or 'Gumdo' (variations of the same pronunciation), and was said 'Kendo' in Japanese. Up until the late 1800's, all three words meant exactly the same thing, and refered to any martial sword art.
In the late 1800's, the Japanese started using the word 'Kendo' to refer only to a sport fencing art, using armor and shinai (bamboo sword). Kenjutsu was used to refer to any other sword art. Meanwhile, back in Korea, 'Kumdo' or 'Gumdo' was still used to refer to any sword art, including the Japanese-style sport fencing using a bamboo sword. Kendo became popular in Korea during the occupation, when Korean martial sports were forbidden, and the Korean police force were trained in Japanese-style martial arts. Today, Kumdo-with-the bamboo-sword (just like Japanese Kendo) is the most widely-known and most practiced of any of the types of kumdo in Korea. Because of this, many people today say that 'kumdo is kendo', because the only Korean sword art they know is the type of 'kumdo' that is exactly like Japanese kendo, except for using Korean terms instead of Japanese terms.
This is probably more 'history' than you wanted, but I thought it was important for background info.
Today there are many active Korean sword arts, all of which are called 'kumdo', and only two of which are anything at all like Japanese kendo. The Korean Kumdo Association, or 'Daehan Kumdo', is exactly like Japanese kendo, and is a member in good standing of the IKF. The Korean Kumdo Federation, or "Hankuk Kumdo", is just like Japanese kendo, but they refuse to admit it, have their separate association, and refuse to be part of the IKF. In addition to these, there is Hankuk Haedong Kumdo, Daehan Haidong Gumdo, Shim Gumdo, Gicheon, Hwarang Gumdo, and nearly a dozen others, all of which use a wooden sword (mok gum) instead of a bamboo sword (chukdo), and none of which look anything like Japanese kendo.
If you want lots and lots of excellent information on all the 'non-kendo' types of kumdo/gumdo, I recommend you visit the
HDGD Forum. For some video clips of some of the different techniques, try
here, bottom half of the page.
As far as the history of haidong gumdo or haedong kumdo (again, alternate spellings reflecting two different associations using the same art), it does not go back thousands of years. It's two main modern leaders studied gicheon (a very rare Korean martial art similar in style to Northern Mantis, with sword techniques that do go back huindreds of years) and shim gumdo (a method of mediation using sword techniques started by a monk in the 1960's. but possibly containing elements of traditional Korean monastic sword arts). So, it is based on some elements from older lineage authentic Korean sword techniques, but the organization of the forms and curriculum is from the 1970's. The organization of the curriculum is part of the genius of the haedong kumdo arts, and it tends to produce excellent cutting technique, as can be seen in the cutting competitions at the national and international levels.
More info can be found at the websites for the
World Haidong Gumdo Federation, the
US Haidong Gumdo Association, and if you can read Korean, the
World Haedong Kumdo Federation
As an aside, I only know of 'Koryo Gumdo' by reputation, and unfortunately, I have not heard good things about it. Also, if kendo is what you want, then you are looking for a school affiliated with 'Daehan Kumdo'.
Gumdo vs. Kumdo
