Isle of Man Steam Packet Company England, Wales, Scotland and Ireland. Ports served included Liverpool, Silloth, Whitehaven, Holyhead, Ardrossan, Blackpool, Belfast and Dublin. Vessels and crews of the company were actively involved in both the First and Second World Wars. One vessel, , was attached to the British Grand Fleet and led the German High Seas Fleet into Scapa Flow in the Orkney Islands at the end of the First World War. Another vessel, "Viking", was converted to become a seaplane carrier, serving as . During the First World War, eleven out of a total fleet of fifteen Steam Packet ships were requisitioned by the Admiralty.
Master of the fleet rank of captain, while masters who had served at least 15 years were given the new rank of "staff commander" and ranked after commander. During the First World War the title was revived for the Grand Fleet's senior Navigation Officer. The title has been used outside the Royal Navy, such as in "Ultramarines" and other science fiction, and for the captain of the "Belle of Louisville". Master of the fleet In the Royal Navy, the rank of master of the fleet denoted the sailing master of a fleet flagship, or the senior sailing master in a fleet. Examples include John