After 1911
The institution of the yamen fell victim to the Wuchang Uprising and the Xinhai Revolution, after which warlords often wound up becoming the ultimate authorities, in spite of Sun Yat-sen's best efforts to establish a Republic of China covering all of China. Sun Yat-sen tried to establish a form of self-government, or home rule, on a regional (or local) basis, but he found that he needed bureaucracy to run a country as big as China. Hence, new bureaucratic offices arose, thus replicating the functions of the Imperial yamens in many ways.
The term yamen is still used in colloquial Chinese today, however, to denote government offices. It sometimes carries negative connotations of an arrogant or inefficient bureaucracy, much as the term "mandarin" does in English.
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