Theodore Bailey was born on May 30, 1808, in Litchfield County, Connecticut, to Theodore and Loraine Bailey. When he was a child, his family moved to New York and then to Pennsylvania. According to an early biographer, at the age of 18, he moved to Erie, Pennsylvania, and “followed teaming.” He married Nancy Chidester in April 1834, and they had a son named James. The family moved to Port Stanley, Canada, around 1842. Then, around 1850, they moved to Alabama, and he worked “in the livery-stable and staging business.”
They moved to Dunkirk, Wisconsin, around 1855, and he purchased a 120-acre farm. In June 1863, he received an appointment as a local postmaster. His son served in the Union army and died in the Battle of Malvern Hill. His wife passed away on June 9, 1868, and he married Emily Lyon on August 25, 1869. The couple had no children together, but he helped raise her two children from a previous marriage. By 1870, he owned $4,000 of real estate and $1,200 of personal property. He died on March 25, 1892.