The Bismarck Sea lies in the southwestern Pacific Ocean to the north of the island of Papua New Guinea and to the south of the Bismarck Archipelago and Admiralty Islands. Like the Bismarck archipelago, it is named in honour of the German chancellor Otto von Bismarck. The Bismarck archipelago extends round to the east and north of the sea, enclosing the Bismarck Sea and separating it from the Pacific Ocean.