Notably, he served briefly as Premier and later President of the Republic of China in the 1920s, and, shortly before his death, became a member of the National Committee of the Chinese People's Political Consultative Conference.

A native of Shanghai and a graduate of the University of Virginia (where he studied political science, received prizes and medals for debate, and was elected to Phi Beta Kappa), he taught English at St. John's University, Shanghai for a short time after coming back from the United States, where he became a Freemason, and then went to Beijing to start his political career.

Wu Peifu handpicked him for the acting presidency to pave the way for Cao Kun's restoration, and he set up a cabinet in anticipation,[3] but he was unable to take office due to Zhang Zuolin's objection.

When Yan finally took his post, he immediately resigned and appointed navy minister Du Xigui as his successor.

In early 1949 he visited Moscow and met with Joseph Stalin, in hopes of negotiating a solution in the Chinese Civil War.