Sessinghaus was born on November 8, 1838 in Köln (Cologne), North Rhine-Westphalia, then part of Prussia.
After pursuing preparatory studies in Germany, he immigrated to the United States and settled in St. Louis, Missouri, a city with a majority German speaking population, where he worked in the milling business.
During the Civil War, he served as a private in Company A, Fifth Regiment, of the United States Reserve Corps, Missouri Volunteer Infantry.
In the 1880 congressional election, he was defeated by Democrat Richard Graham Frost in Missouri's third district.
Congress did not decide in his favor until the penultimate day of the legislative period, on March 2, 1883.