William Siemens was one of the founding personalities of Siemens as a company. Born in Germany, he emigrated to England, where he earned a multitude of honors and respect. He led the Siemens business in England in addition to his activities as an independent engineer and entrepreneur. Among other areas, he worked on the global telegraphy system and metallurgical innovations as well as issues related to energy savings and protecting the environment. His name is associated with the Siemens-Martin process, the world’s most important process for steel production for an entire century. With this biography, Wolfgang König brings to life an era in which industrialization came of age and globalization began to change the face of the world. William Siemens and his brothers Werner and Carl formed a “league of siblings“ that created the global company, Siemens. William was, in particular, responsible for building up the English business. He was instrumental in the company’s commitment to transoceanic telegraphy, which was a major contributor to the globalization of the 19th century. Among the Siemens brothers, he stood out as an exception on many fronts: He was not an electrical engineer but rather a trained mechanical engineer; he emigrated from Germany and became an English citizen; and, in addition to his responsibilities within Siemens, he was also an independent inventor and entrepreneur. The biography by Wolfgang König paints a fascinating picture of a successful entrepreneur, inventor, and engineer who was at home in multiple disciplines as well as in two distinct national cultures. With this work, König also contributes to a cultural comparison between the two industrialized nations of Germany and England.