Genocide refers to the intentional and systematic annihilation of a specific group of individuals based on their ethnicity, nationality, religion, or race. The term combines the Greek word "genos," meaning "race," "tribe," or "nation," with the Latin "cide," which translates to "killing." This concept was introduced by Raphael Lemkin, a jurist of Polish descent who served as an advisor to the U.S. Department of War during World War II.
While the term itself emerged in the 20th century, acts of genocide can be traced throughout human history, though some scholars argue that its classification should be confined to only a select number of instances. For example, the historian Thucydides documented the massacre of the Melian population by the Athenians during the Peloponnesian War when they refused to capitulate. Historically, it was not uncommon for victorious armies to execute all the men of their conquered foes. The systematic persecution and slaughter of the Cathari during the Albigensian Crusade in the 13th century is occasionally referenced as one of the earliest examples of genocide in the modern sense, yet many medieval historians are wary of applying this label.