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.
Naval warfare in the Mediterranean during World War I to bombard the cities of Bizerte and Bône in the French protectorate of Tunisia. Pursued by larger French and British forces, the "Goeben" and "Breslau" ran for Turkey, where they were nominally transferred to the Ottoman Navy when the Ottoman Empire entered the war on the Central Powers side, and fought several battles against the Russian Black Sea Fleet until Russia's surrender in 1917. After the Kingdom of Italy entered the war on the Allied side in 1915, the strategy of the Allies was to blockade the Adriatic at the Otranto Straits and monitor the movements of the Austrian fleet.