The Horn of Africa dominates today’s headlines. From ethnic cleansing in Ethiopia’s Tigray region to the ongoing war against al Shabaab, the region is beset by overlapping crises. Understanding today’s tumult in the Horn requires grappling with the complex legacy of the Cold War’s final chapter in the region. The Cold War accelerated and intensified the Horn of Africa’s zero-sum brand of ethnic politics from 1977-1985, and the thaw and subsequent end of the Cold War in Africa ended critical lifelines for the notorious regimes in Addis Ababa and Mogadishu, precipitating their collapse in 1991. This essay outlines how the Cold War’s conclusion laid the groundwork for the Horn’s bloody 21st century.