Aegon's Conquest

Aegon's Conquest was the war in which Aegon Targaryen, with his sister-wives Rhaenys and Visenya and the dragons Balerion, Meraxes and Vhagar, brought six of the Seven Kingdoms of Westeros under one crown within two years. Only Dorne held out. Some houses surrendered or joined him instead of fighting. Aegon was crowned by the High Septon, beginning roughly three centuries of Targaryen rule, and the Westerosi calendar counts years from his coronation.