Chagdarjav was born in 1880 in present-day Selenge Province. He was a member of the quasi-provisional government established in Khüree in 1911 as the Qing dynasty of China was collapsing and was later appointed Minister of Finance under the Bogd Khan's first government. He took part in negotiations during the Kyakhta Conference in which Mongolia sought international recognition of its status as an independent state, but ultimately had to settle for recognition of a "de facto" autonomy under Chinese auspices.