The first use of the expression "Silk Road" -- actually "Silk Roads" appears to have been in German: Die Seidenstrassen. Geographer Baron Ferdinand von Richthofen (1833-1905) used the expression "silk roads" to describe the trade routes linking China, India, the Mediterranean world via central Asia, according to "Silk Roads or Steppe Roads? The Silk Roads in World History," by David Christian, in Journal of World History 11.1 (2000) 1-26.
