Finkel was born in Ohio to German immigrant parents in 1854. He and others claimed that he enlisted in the United States Army in the early 1870s and served under George Custer during the Great Sioux War of 1876. During the Battle of the Little Bighorn, Finkel claims he was wounded early in the fighting and his horse bolted from the battle. After being nursed back to health, he traveled to St. Louis, then settled in Columbia County, Washington. Over the next 40 years, he amassed a significant estate as a farmer in the town of Dayton and came to be regarded as one of Dayton's "pioneers". Sometime around 1920, he began telling companions that he survived the Battle of the Little Bighorn, and for the next several years recounted his alleged experiences in the battle.