Operation Chahar
Operation Chahar (Japanese: チャハル作戦, romanized: Chaharu Sakusen), known in Chinese as the Nankou Campaign (Chinese: 南口戰役; pinyin: Nankou Zhanyi), occurred in August 1937, following the Battle of Beiping-Tianjin at the beginning of Second Sino-Japanese War. This was the second attack by the Kwantung Army and the Inner Mongolian Army of Prince Demchugdongrub on Inner Mongolia after the failure of the Suiyuan Campaign.