A career Army officer of Swiss origin. He and his wife were in the Whitefield-Lady Huntingdon circle and through it came to know Charles Wesley, his family and John Wesley. From Manchester in 1749, Mrs Gallatin sent gifts to William Grimshaw for his work, and in 1751 Gallatin invited John Wsley to Musselburgh. John and Charles Wesley both stayed with them at Lakenham during their first visit to Norwich in 1754, while working on the Explanatory Notes upon the NT, and heard from them of James Wheatley's conduct. The Gallatins retired to Ham (Kent) and on Gallatin's death Charles Wesley called this 'bosom friend' 'gentle, generous and sincere'.