While the Revolutionary and Civil wars have been the object of much research and documentation, the war that bridged them has been largely neglected. This is a comprehensive research guide to the careers and manuscript sources for President and Commander-in-Chief James Madison, his three secretaries of war, nine major generals, 27 brigadier generals, various departments, five artillery regiments, three cavalry regiments, the Corps of Engineers, 48 infantry regiments, and four rifle regiments of the United States during the War of 1812. Each unit has a history and a listing of archival resources. A directory of more than 100 manuscript repositories and their addresses is included.