Mengjiang Mengjiang ( ; Postal map spelling : Mengkiang ; Hepburn : Mōkyō ) , also known in English as Mongol Border Land , was an autonomous area in Inner Mongolia , existing as a puppet state of the Japanese Empire under nominal Chinese sovereignty . Formed in 1939 , it consisted of the then - Chinese provinces of Chahar and Suiyuan , corresponding to the central part of modern Inner Mongolia . It is occasionally called Měnggǔguó ( 蒙古國 ) or Mengkukuo ( in analogy to Manchukuo , another Japanese puppet state in Manchuria ) . The capital was Kalgan , and the ruler was Demchugdongrub . The territory returned to Chinese control after the defeat of the Japanese Empire in 1945 . Background . Following Japan ’ s occupation of Manchuria in 1931 and the establishment of the puppet state of Manchukuo , Japan sought to expand its influence in Mongolia and North China . In a series of actions , starting in 1933 , the armies of Manchukuo and Japan occupied Chahar and in 1936 proclaimed itself the independent Mongol Military Government , allied with Japan under Prince Demchugdongrub . In 1936 and 1937 , similar operations in Suiyuan saw the occupation and absorption of that province also . History . Formed on 12 May 1936 , the Mongol Military Government ( 蒙古軍政府 ) had Prince Yondonwangchug of Ulanqab as its first chairman . It was renamed in October 1937 as the Mongol United Autonomous Government ( 蒙古聯盟自治政府 ) . On 1 September 1939 , the predominantly Han Chinese governments of South Chahar and North Shanxi were merged with the Mongol United Autonomous Government , creating the new Mengjiang United Autonomous Government ( 蒙疆聯合自治政府 ) . The capital was established at Zhangbei ( Changpei ) , near Kalgan ( Zhangjiakou ) , with the government ' s control extending around Hohhot . On 4 August 1941 , it was again renamed : the Mongolian Autonomous Federation ( 蒙古自治邦 ) . After Wang Jingwei formed a new government for the Republic of China in Nanjing , Mengjiang was placed under its control , though it remained completely autonomous . Mengjiang ceased to exist in 1945 when it was invaded by the Soviet Red Army and Mongol Red Army as part of the Manchurian Strategic Offensive Operation . Most of the area , with the notable exception of Kalgan , is now part of Inner Mongolia in the PRC . Name . " Mengjiang " , meaning " Mongolian Territories " , came from the acceptance speech of chairmanship by Demchugdongrub : Economy . The Japanese established the Bank of Mengjiang that printed its own currency without years on it . Some traditional local money shops also made currency with Chinese year numbering system , such as the Jiachen Year ( 甲辰年 ) , on it . The Japanese had mineral interests in their created state of Mengjiang . One example was Japanese put in production the iron mine in Hsuanhua – Lungyen with a reserve of 91 , 645 , 000 tonnes in 1941 ; and analyzed the reserves of coal in land , one 504 tonnes and one potential production of 202 , 000 of tonnes ( 1934 ) . The Mengjiang iron deposits were exported directly to Japan . At the same time , Japanese seeking the coal reserves of Suiyuan ( another Mengjiang occupied sector ) including one of 417 million tonnes and one potential extraction of 58 , 000 tonnes in 1940 for future investments in that area too . Military . The Mengjiang National Army was the Japanese created " native army " organized in Mengjiang ; not to be confused with the Mongol Army . It was a Kwantung Army special force group under direct command , having native commanders alongside Japanese commanding officers , as in other auxiliary outer sections of the Kwantung Army . The purpose of the army was to support any eventual Japanese operations against Outer Mongolia ( Mongolian People ' s Republic ) , or the north China areas , and to act as a local security force , with the local police forces . It also had the duty of protecting Prince De Wang , the head of state , and the Mengjiang native establishment and local government properties . The army was equipped with rifle s , pistol s , light and medium machine gun s , mortar s and some artillery and anti - aircraft gun s . It was organised as a mobile cavalry and light infantry force with little artillery support and no tank s or aircraft . History . In 1936 , the Inner Mongolian Army was armed with Mauser rifles and they had 200 machine guns : mostly the Czech ZB - 26 and a few Swiss Sig . Model 1930 sub - machinegun for Teh Wang ' s 1 , 000 bodyguard troops . They had 70 artillery pieces , mostly mortars and a few captured Chinese mountain and field guns of a variety of types ( making ammo and spare parts a problem ) . The few tanks and armored cars were captured Chinese vehicles crewed by Japanese . After the Suiyuan Campaign , the Mengjiang National Army was rebuilt from the defeated remnants of the Inner Mongolian Army , the new eight Mongol cavalry Divisions were 1 , 500 men strong , in three regiments of 500 men . Each regiment were to have three Saber companies and a Machinegun Company of 120 men . However these divisions actually ranged in size from 1 , 000 men to 2 , 000 men ( 8th Division ) . In 1939 , the ethnic Chinese troops in the Mongol Divisions were brigaded together in the 1st , 2nd and 3rd Divisions and turned into the 1st , 2nd and 3rd Ch ' ing An Tui Brigades of the " Mongolian Pacification Force " and used against various guerrilla groups . In 1943 , the Mongol 4th and 5th Divisions were combined to form a new 8th Division and the old 7th and 8th Divisions formed the new 9th Division . Strength of the army was between 4 , 000 - 10 , 000 men , all cavalry at this time and had little heavy equipment and that controlled by the Japanese . The Mengjiang state also had 5 Defense Divisions in 1943 , made up of local militia and other security forces , nominally of three regiments . Apparently only one of these regiments in each division was capable of operations . In 1944 , the Japanese reorganized them along with the Chahar garrisons into four Divisions of 2 , 000 men each . At the end of the war , a total of six divisions ( two Cavalry and four Infantry ) , three Independent Ch ' ing An Tui Brigades and a " Pao An Tui " Security Force Regiment made up the Army .