Louis Bell was descended from John Bell, a staunch Scotch-Irishman who in 1719 left County Antrim, Ireland, to join, in 1720, the small colony of his countrymen already settled at Londonderry in the southeastern corner of New Hampshire. Here the family prospered and became prominent in the public affairs of county and state. The grandfather of Louis Bell was Samuel Bell, twice elected senator from New Hampshire and Daniel Webster's intimate friend, while his father was Col. Louis Bell, educated at Brown University, a man of commanding physique, clear head, and scientific tastes. In the final charge by which the Union troops captured Fort Fisher, North Carolina, on January 15, 1865, Col. Bell took part, and died of wounds received in action on that day. It is little wonder that the son, then only six weeks old, always regarded his father as a hero. His broken-hearted mother, Mary Ann Persis (Bouton) Bell, died a few months later; the boy Louis and his sister, four years older, grew up in the home of their grandmother, the widow of Gov. Samuel Bell, at Chester, New Hampshire.