The East Coast Brotherhood of Steel is a chapter of the Brotherhood of Steel and was founded by Elder Owyn Lyons. Their headquarters is the Citadel, an imposing fortress built into and beneath the ruins of the Pentagon on the edge of what used to be Washington, D.C. As of 2287, they are led by Arthur Maxson, the last descendant of the venerated Maxson family line. Under his leadership, the Brotherhood has grown into a major military power in the region, able to project their power and influence all along the Eastern Seaboard.