A warlord is a person with power who has both military and civil control over a subnational area due to armed forces loyal to the warlord and not to a central authority. The term can also mean one who espouses the ideal that war is necessary, and has the means and authority to engage in war. Today, the word has a strong connotation that the person exercises far more power than his official title or rank legitimately permits. Under feudalism, by contrast, the local military leader may enjoy great autonomy and a personal army, and still derive legitimacy from formal fealty to a central authority.
Warlordism is a term coined to describe chaos at the end of the Qing Dynasty and the birth of the Republic of China, from the death of Yuan Shikai in 1916 until 1928. This period is called the warlord era of China. It can however be used to describe similar periods in other countries or epochs such as in Japan during the Sengoku period, or in China during the Three Kingdoms, or in Somalia during the Somali Civil War.
The word "warlord" entered the English language as a translation from the German word "Kriegsherr", which was an official title of the German Emperor. Its use for Chinese military commanders who had a regional power base and ruled independently of the central government dates from the early 1920s, with Bertram Lenox Simpson being one source, according to the Oxford English Dictionary.