"How many Border Wars have there been? Five? Six? I lost count."
Trevyr Blackgard on the Border wars
A Border war is a war where the entirety of the Borderlands (including House Blackgard; their vassals, and the majority of the Borderlands' population) is involved in a major military conflict. A Border war tends to be long, bloody and brutal, resulting in the deaths of many, if not all soldiers.

There have been seven border wars to date. The seventh and current border war began when Steffon Blackgard orchestrated the Black Day and crowned himself Black King of Ebonheart after killing his uncle, Eddin Blackgard, who had been the reigning Lord of Ebonheart. This split House Blackgard into two factions (one lead by Steffon and the other lead by his great aunt, Sofina Blackgard) who are currently fighting for control of the Borderlands.

The timeline and the major events of the first five border wars have been chronicled in the book As Blood Runs Black: A Compendium of the Border Wars, written by Archmaester Vespasian.

List of border wars