Paul Hoffmann was an officer of the Imperial German Navy (Kaiserliche Marine), who rose to the rank of vice-admiral. In 1889 he was captain of the SMS Kaiser, the lead ship of the Kaiser-class armored frigates commissioned on 13 February 1875. From 21 October to 12 November 1889, he had Emperor Wilhelm II as his guest during the Emperor's Mediterranean tour visiting Genoa, Athens, Istanbul and Venice. His dairy entries from that period are interesting to the study of the Emperor's personality and enthusiasm for naval matters, and for the later service of the Emperor's brother Prince Heinrich in the Mediterranean.