Bay State was the brand name of high end acoustic guitars created by the John C. Haynes Company, which was founded in 1865 in Boston, Massachusetts. The importance and historical significance of the John C. Haynes Company and its parent company, the Oliver Ditson Co., on the development of musical tastes and expectations of the American people in all things "guitar" should not be underestimated. They were arguably the first manufacturer of stringed instruments producing significant numbers for the general population (C.F. Martin and Co., while established in 1833, did not start producing large numbers of instruments until the 1890’s, and it appears their total production from 1833 to 1900 was around 10,000 guitars. This compares to approximately 30,000 guitars produced by the Haynes company from 1865 to 1903).
Many significant personalities who influenced the developing music industry started work with John Haynes including P. J. Healy and George Washburn Lyon. Oliver Ditson helped them set up their firm of Lyon & Healy in Chicago in 1864.