Fratricide

Fratricide is the killing of one's own brother, a term drawn like the atlas's other family-killing offenses from Latin, joining frater, brother, to the same -cide root used for mariticide and sororicide. The concept recurs across religious and mythological traditions as the archetypal act of family betrayal, from the biblical account of Cain and Abel to the founding myth of Rome, in which Romulus kills his twin brother Remus in a dispute over the city's location and naming. Historical instances include the Roman emperor Caracalla's murder of his co-emperor brother Geta in AD 211, and the Ottoman Empire's formal legalization of fratricide by Mehmed II, who held that a sultan could lawfully execute his brothers to prevent succession disputes from weakening the state; the practice was later abolished by Ahmed I in favor of a seniority-based succession system. In modern usage the term also applies in a military sense to a service member's killing of a fellow combatant, and is used metaphorically to describe civil wars fought among people of a single nation. Like other family-homicide categories in this atlas, fratricide is prosecuted under ordinary homicide statutes rather than as its own distinct offense.