Korean soju is distilled from fermented rice, or optionally wheat, barley, sweet potatoes, or tapioca. It is believed that it initially appeared when Mongols introduced the distilling technique to the Koreans, sometime in the 13th century.
The first varieties were made with rice, but in 1965 Korean government introduced a ban on using rice, and many producers looked for alternative sources. Soju is a clear spirit that is usually low in alcohol and has a mild, neutral flavor, which makes it work well with a wide array of dishes.