The War of the Mark was a terrible and bloody conflict which changed the face of Khorvaire, solidifying the dragonmarked houses' position today. The war began about five hundred years before the establishment of Galifar, when the dragonmarked houses launched an inquisition to put an end to the proliferation of aberrant and mixed dragonmarks. References: Eberron Campaign Setting. James Wyatt, Keith Baker, Ari Marmell, Robert J. Schwalb (2009). Wizards of the Coast.