Born at Heilbronn, Wurtemburg, Arnold settled in New Orleans by 1850. In New Orleans city directories, he is listed variously as a lithographer, fancy painter, sign painter, artist, and painter of portrait, landscape, and marine subjects from that year until his death, which occurred on October 14, 1866.

Painting the Confederate defeats at Port Hudson and Mobile Bay, Arnold recorded two of the South’s most devastating losses of the entire War, which taken together, effectively left the Confederacy cut off from foreign trade, upon which its very survival depended.

In addition to the public collections mentioned above, Arnold’s work is represented in The Mariner’s Museum, Newport News, Virginia; Florence Museum of Art, Science and History, South Carolina; Shelburne Museum, Vermont, and the Peabody Museum of Salem, Massachusetts.