This study investigates the influence of Western music on Whistler’s artistic theory and practice. Drawing upon primary sources, it traces Whistler’s lifelong exposure to, and engagement with, music making, and considers the ways in which he translated his musical experiences into pictorial subject matter. Whistler’s use of musical nomenclature and analogy are then examined, within the context of both his personal musical experience and knowledge, and the wider nineteenth-century interest in the interrelations between the visual arts and music. The notions of musical autonomy, art-for-art’s sake and artistic correspondence; the influence of music on colour theory; and the discourse of enthusiasm surrounding Beethovenism and Wagnerism are deemed influential.