Prince Demchukdongrub led the last effort to create a pan-Mongol monarchy during World War II. He is often known as Prince Teh or Prince De Wang. The last Qing Emperor of China gave him the title of "Prince Teh the Martial" for his longtime loyalty to the Qing dynasty. Demchukdongrub was the only son of Prince Namjil Wangchuk of the White Banner in Chahar province, Inner-Mongolia. He married into the Manchu nobility and was able to stay in the good graces of General Yuan Shihkai after the fall of the Qing Empire. He became a local leader in Chahar province and was in contact with many agents, societies and individuals who wished to promote monarchism and solidarity between Manchuria, Japan and Mongolia. Prince Teh, like most all Mongol leaders, claimed descent from Genghis Khan and had long advocated the unification of all his people into a pan-Mongol monarchy.
In September of 1933 the princes of Suiyuan and Chahar provinces joined together to form a provisional government and sent word to the government of the Republic of China that if full autonomy for Inner Mongolia was not given to them they would seek aid from Japan. The Chinese nationalists were naturally opposed to this but could do little about it. Help did come in from the commander of the Japanese Kwantung Army in Manchuria and strong ties were also easily established with the restored Manchu Emperor of Manchukuo. In 1936 the Japanese sponsored the formation of the Autonomous Mongolian Military Government under Prince Teh assisted by a Japanese advisor. A long-term ideal would have obviously been unity with Outer Mongolia. However, ever since the defeat of the Russian monarchist Ungern-Sternberg Outer Mongolia had been ruled by a communist-client regime of the Soviet Union though some monarchist princes were able to attend pan-Mongol meetings in Inner Mongolia.
Prince Teh established the provisional Inner Mongolian monarchist state known as Mengjiang but had to devote most of his time to military buildup to support the Japanese war effort on which all of their hopes for the future depended. Of course this would doom them in the eyes of many future generations but all knew that there would be no hope for an independent Mongol monarchy if either faction of the Chinese republicans won the war. For a time things went well with their territory expanded through campaigns alongside the Japanese and Manchurians. A more solid and better organized government was set up but, of course, it could not survive the defeat of Japan in 1945. Prince Teh was arrested by the Kuomintang and kept in Peking for four years. When the communists were on the verge of winning the Chinese Civil War in August of 1949 Prince Teh was able to return to Inner Mongolia and tried to set up another autonomous government. The People's Liberation Army finally forced him to flee to Outer Mongolia where the people welcomed him as a pan-Mongol hero but the local communist government arrested him and turned him over to the Red Chinese.
Prince Teh was convicted of treason by the Chinese communists and thrown in prison as a war criminal for collaboration with the Japanese. Like the last Emperor of China he wrote his memoirs while in prison and was pardoned 13 years later. He returned to Inner Mongolia and worked in museum. He died in Hohhot on May 23, 1966 still a national hero in the hearts of many Mongolians who dreamed of independence and unity for all of their people.