After looking at all the hoops that you have to jump through to get married in Korea when one of you works for the US government, you might want to look into other options, such as getting married back home, eloping, or a proxy marriage. I have information about the latter two: eloping and proxy marriages.
The US Embassy has more information about marriage in Korea. You won't be getting married at the embassy or on base. Most people get married at the gucheon (district office). It's a civil ceremony. Religious ceremonies aren't legal in Korea.
You will get a Korean marriage certificate and will probably need to have it translated, notarized, and apostillized if you want to use it outside of Korea. Check with your state back home to see if you can record (not register, it's semantics) your foreign marriage there. Some states no longer do this. Since my husband and I are both Americans, we decided against getting married in Korea specifically because we wanted an American marriage certificate.
Before you get married, there are certain things that you should discuss. Here are some questions that although they are aimed at military couples, they still pertain to many couples. There are also many books with questions you should discuss before you get married.
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