May 3, 1809, Hudson, New Hampshire.
July 1, 1890, Hudson, New Hampshire.
Marshall is sometimes confused with his son, Leonard Babbidge Marshall (born 1847).
Leonard the elder was a voice pupil of John Paddon of London and harmonist Charles Zeuner.
He was principal tenor soloist for the Handel and Haydn Society in Boston, Massachusetts (circa 1844–50); music director at the Twelfth Congregational Church, Boston (circa 1836–57); chorus director at Tremont Temple (1857–67); music director at the Bowdoin Square Baptist Church (circa 1867–70); Charles Street Baptist Church; Harvard Street Baptist Church (circa 1870–75), and other Boston churches.
His works include 13 church music books and: