The Bismarck Archipelago is a group of islands off the northeastern coast of New Guinea in the western Pacific Ocean and part of Papua New Guinea.
The first inhabitants of the archipelago arrived around 33,000 years ago after they sailed from what is now Papua New Guinea. Later arrivals included the Lapita people.
The first European to visit the islands was the Dutch explorer Willem Schouten in 1616.
The islands remained unsettled by Western Europeans until they became part of the German protectorate of German New Guinea in 1884. The area was named after German Chancellor Otto von Bismarck.
On 13 March 1888, a volcano erupted on Ritter Island causing a megatsunami. Almost all of the volcano fell into the ocean, which left a small lake in the volcanic crater.
Afer the outbreak of World War I, the Australian Naval and Military Expeditionary Force seized the islands in 1914 and Australia later received a League of Nations mandate for the islands. They remained under Australian control (interrupted only by the Japanese occupation during World War II) until Papua New Guinea became independent in 1975.