German New Guinea () consisted of the northeastern part of the island of New Guinea and several nearby island groups and was the first part of the German colonial empire. The mainland part of the territory, called Kaiser-Wilhelmsland, became a German protectorate in 1884. Other island groups were added subsequently. New Pomerania, the Bismarck Archipelago, and the northern Solomon Islands were declared a German protectorate in 1885; the Caroline Islands, Palau, and the Mariana Islands were bought from Spain in 1899; the protectorate of the Marshall Islands was bought from Spain in 1885 for $4.5 million by the 1885 Hispano-German Protocol of Rome; and Nauru was annexed to the Marshall Islands protectorate in 1888.