Edwin S. Johnson (February 26, 1857 - July 19, 1933) was a United States Senator from South Dakota. Born near Spencer, Indiana, he moved with his parents to Osceola, Iowa, in 1857 and attended the public schools. He engaged in the mercantile business, and moved to Wheeler County, Nebraska in 1880 where homesteaded and engaged in agricultural pursuits. He returned to Osceola, in 1881 and was employed as a bank cashier; in 1884, he moved to South Dakota and established the Citizens' Bank of Grand View, South Dakota, and also engaged in agricultural pursuits. He later established a number of banks in South Dakota, Minnesota, and Iowa. He studied law, was admitted to the bar in 1888 and practiced; he was prosecuting attorney of Douglas County in 1892-1893 and was a member of the South Dakota State Senate in 1894-1895. He retired from the banking business in 1902 and engaged in the real estate and loan business at Platte, South Dakota; he was a member of the Democratic National Committee from 1904 to 1916.
Johnson was an unsuccessful Democratic candidate for Governor in 1912, but was elected as a Democrat to the U.S. Senate in 1914 and served from March 4, 1915, to March 3, 1921. He declined to be a candidate for renomination in 1920. While in the Senate, Johnson was chairman of the Committee on Revolutionary Claims (Sixty-fourth and Sixty-fifth Congresses). He resumed his activities in the real estate and loan business and died in Platte in 1933. Interment was in Pleasant Ridge Cemetery, Armour, South Dakota.