Stephenson was born in Hartland, New Brunswick, Canada and moved with his parents to Maine, and later, in 1846, to Delta County, Michigan. He engaged in lumbering and moved to Menominee, Michigan in 1858. He was interested in real estate, lumbering, general merchandising, and agricultural pursuits. He built the Menominee Hotel in 1881 to accommodate visiting lumber buyers; the structure burned down in 1977. After leaving Congress, Stephenson resumed the lumber business. He died in Menominee and is interred there at Riverside Cemetery.
Stephenson served as a member of the Michigan House of Representatives in 1877 and 1878. He also served in the Michigan Senate in 1879, 1880, 1885, and 1886. He was a delegate to the Republican National Conventions in 1884 and 1888.
In 1888, Stephenson was elected as a Republican from Michigan's 11th congressional district to the 51st United States Congress and was re-elected in 1890 to the 52nd Congress. After redistricting due to the 1890 census, Stephenson was elected from the newly created 12th district in 1892 and 1894. In all, he served from March 4, 1889 to March 3, 1897 in the U.S. House.
He served as chairman of the board of supervisors of Menominee County for several years.
|U.S. House of Representatives|
Henry W. Seymour
| United States Representative for the 11th Congressional District of Michigan
1889 – 1893
| United States Representative for the 12th Congressional District of Michigan
1893 – 1897
Carlos D. Shelden