Samuel Joshua was a Londoner and successful merchant. He retired to Felixstowe in Suffolk.
He was the proprietor of the firm of Joshua Brothers, who had offices in 1860 at 39 Clement's Lane, in 1861-1862 at 33 Queen's Lane, and later at 4 Great Winchester Street. The firm were merchants and agents for the Australian Marine Insurance Company. Joshua was invited to attend the Criterion dinner in honour of Whistler in 1889, and may have been a patron or potential patron.
Post Office Directory, London, 1860, 1861 and 1862; UK census 1881, from http://www.familysearch.org (accessed 2004).