The term heleer (speech/language) might also refer to . Mongol armies used a sophisticated system of horn signals and banners (the sulde ). At Jangsari, the student soldiers had no radios (batteries died in the saltwater). They reverted to ancient methods:
In the early 13th century, the Mongol Empire, under the leadership of Genghis Khan and his successors, embarked on a campaign of conquest that would eventually stretch from China to Eastern Europe. One of the key theaters of this expansion was the Korean Peninsula, where the Mongols clashed with the Goryeo Dynasty. A significant, albeit lesser-known, battle in this conflict was the Battle of Jangsari, fought in 1231. battle of jangsari mongol heleer
