The Sierra Leone Civil War (1991–2002), or the Sierra Leonean Civil War, was a civil war in Sierra Leone that began on 23 March 1991 when the Revolutionary United Front (RUF), with support from the special forces of Liberian dictator Charles Taylor's National Patriotic Front of Liberia (NPFL), intervened in Sierra Leone in an attempt to overthrow the Joseph Momoh government. The resulting civil war lasted almost 11 years, and had over 50,000, up to 70,000, casualties in total; an estimated 2.5 million people were displaced during the conflict.

Sierra Leone, officially the Republic of Sierra Leone, is a country on the southwest coast of West Africa. It shares its southeastern border with Liberia and is bordered by Guinea to the north. With a land area of 71,740 km2 (27,699 sq mi), Sierra Leone has a tropical climate and with a variety of environments ranging from savannas to rainforests. According to the 2015 census, Sierra Leone has a population of 7,092,113, with Freetown serving as both the capital and largest city. The country is divided into five administrative regions, which are further subdivided into 16 districts.