Ohio was a major contributor to the success of the War of 1812, in both men and material, but the accomplishments of those men who served in the state militia and in the regular army are not generally recognized. Most persons when researching their War of 1812 ancestors tend to limit their endeavors to militia records in the Roster of Ohio Soldiers in the War of 1812 and to the published indexes of pension records and service records. Approximately 24,000 Ohioans served in this war. They served in the state militia and in the U.S. Army. The army raised the 19th, 26th and 27th Regiments of Infantry from within Ohio, and many Ohioans enlisted into the 1st, 7th, 17th, 24th and 28th Regiments of Infantry, and later the 2nd Regiment of Rifles. Ohio also raised a company of artillery, two companies of rangers, and contributed to the raising of a company of dragoons and four more rifle companies for the army. Many people neglect to search army documents for their ancestors. The key to finding the military records of your ancestor lies in knowing in which company your ancestor served. Hopefully, this book will remove some of the mystery of researching War of 1812 ancestors who lived and fought in Ohio. Eric Eugene Johnson is a lineal descendant of five veterans of the War of 1812 and he is the past president of the Society of the War of 1812 in the State of Ohio (2008-2011).