We present a synopsis of the major trends of Siebold's life, his youth in the Rhineland and his lengthy employment as a physician and natural scientist in the colonial government of the Dutch East Indies. We follow his career on the cramped Japanese island of Dejima where he was based for 6 years. We reveal how, during two visits to Japan, Siebold became a renowned ethnographer, natural historian, author and entrepreneur and an unsuccessful diplomat. In this paper we attempt to provide an insight into Siebold's varied life in Bavaria, The Netherlands and Japan.