Galliard studied composition under Jean-Baptiste Farinel, the director of music at the Court of Hanover, and Abbate Steffani.
Galliard became a familiar face in high society due to his proximity to and frequenting of the royal residence.
In response to war victories, Galliard composed a Te Deum, Jubilate, and three additional anthems.
He wrote the music to the opera Calypso and Telemachus upon the request of a friend, the poet John Hughes.
He published an opera, music to the Morning Hymn of Adam and Eve taken from John Milton’s Paradise Lost, and a large number of pantomimes which he devised under contract to Rich, the enterprising manager of the Lincoln’s-Inn-Fields Theatre.