Samuel Swain (SS) Stewart was born in Philadelphia in 1855. He kept a music store in Church Street and was both an instrument maker and music publisher and had a dream to see the banjo accepted as a serious and classical instrument rather than just a black American folk instrument or a Minstrel instrument. He tried changing the spelling of banjo (banjeau) to this end, as well as sponsoring musicians who could read music.
He made banjos from around 1878 under his own name, and also the Acme brand for Sears. he introduced many innovations in banjo construction and is also credited with inventing the Banjeaurine about 1885- a small scale banjo intended to play lead melody in banjo orchestras.
Stewart banjos led the field until the tone ring was invented in the 1890's by A C Fairbanks. That saw the rise of Fairbanks, Cole and then Vega. Stewart died in 1898 at the age of just 43 but had probably made over 25,000 banjos of all sizes and styles.
The SS Stewart banjo continued to be made by his partner George Bauer, a guitar and mandolin maker, until around 1910. Stewart's sons (one of whom was Fred. S Stewart) also manufactured some banjos around the turn of the century. The name and the banjo survived a buy-out for another five years or so. The name lived on longer with both Gibson and Lange producing banjos with an SS Stewart name.