It appears that your ancestor was a member of the 1st Regiment of US Rifles, which was a part of the regular army. 500 men were recruited from Kentucky and southeastern Ohio for this regiment. The regular army kept far better records than the militia. You will need to get NAFT Form 85 (Military Service Records) from the National Archives and mark “regular” for army service in Box 9 (Kind of Service). The National Archives has the consolidated enlistment rosters for all of the U.S. Army regiments that served during the war in book form. This book is called the Records of the Men Enlisted in the U.S. Army Prior to the Peace Establishment, May 17, 1815. This book contains the name and rank of each enlisted personnel, his regiment, his company commander’s name, his regimental commander’s name, a physical description of your ancestor plus his peacetime occupation, where he was born (county and state, or country), where he enlisted and the period of enlistment, and any additional remarks. All of the columns may not be filled in. A page from this book will be sent to you as your ancestor’s service record. On NAFT Form 86 (Military Pension/Bounty Land Warrant Applications) mark “regular” for army service in Box 8 (Kind of Service) to obtain his bounty land warrant. William may have served in the militia before he joined the regular army. You can also get his militia service records from the National Archives.