After the
Wuchang Uprising broke out in 1911, Jiang accepted an invitation from his friend, , the Governor of
Zhejiang Province, to serve as the chief adviser in his office. Later on,
Yinchang recommended Jiang to
Yuan Shikai. In 1912, Jiang was appointed as the principal of the
Baoding Military Academy. He attempted suicide in 1913 after failing to obtain the funding he had promised to get for his students. He was saved in time by his bodyguards and earned himself a reputation for regarding keeping his promises as more important than his life. In 1913, he became a first-class military adviser to Yuan Shikai, who had become the
President of the newly established
Republic of China. He wrote
New Interpretations of Sun Tzu (孫子新釋) in the following year. In 1916, after Yuan Shikai declared himself emperor and created the short-lived
Empire of China, Jiang strongly objected to Yuan's decision and fled from
Beiping to
Guangdong Province. He joined the warlord
Cai E in attacking Yuan Shikai and served as the chief adviser of the combined military forces of Guangdong and
Guangxi provinces in the campaign against Yuan, who died later that year. Jiang accompanied Cai E, who was ill, to Japan to seek medical treatment, but Cai still died of illness eventually. In 1917, Jiang became a consultant in the office of
Li Yuanhong, who had succeeded Yuan Shikai as President of the Republic of China. During this time, he wrote
Common Knowledge About the Military (軍事常識). In the subsequent years, Jiang spent his time mainly on writing books, editing magazines and involvement in societies for literature and poetry appreciation. In 1918, he followed
Liang Qichao on a study tour to Europe and became active in the
New Culture Movement after returning to China in 1920. In 1925, he travelled to
Hankou, where he became chief-of-staff to the warlord
Wu Peifu. He urged Wu Peifu to ally with the
Nationalist government in Guangdong Province to fight the warlord
Zhang Zuolin, but Wu rejected his suggestion. He left Wu Peifu in 1926 after the latter decided to ally with Zhang Zuolin's
Fengtian Clique against
Feng Guozhang's
Zhili clique. He then travelled to Shanghai to join
Sun Chuanfang, but decided to leave after Sun allied with Zhang Zuolin. ==Service under the Nationalist government==