The first human inhabitants of Nosy Be were small bands of Antankarana and Zafinofotsy, before the Sakalava migrated there and became the most numerous ethnic group on the island. These people were joined later by some Comorians, Indians or Antandroy.

Nosy Be made first major appearance in Madagascar’s history when King Radama I announced that he intended to conquer the whole west of the red island up to the sea. That plan was eventually achieved when the Sakalava Kingdom of Boina came into his possession in 1837 when Queen Tsiomeko of Boina’s army was defeated. The French colonized the island from 1840, founding an outpost named Hell-Ville (from French Admiral de Hell). In 1849, slavery was abolished by the French, though the slaves were owned by Malagasies. It caused a Malagasy revolt against the French. In the late 19th and early 20th centuries, the island was ruled by the French, using military force and diplomacy to maintain their position in the Island. Though it was difficult for the French to control the littoral, they found a plantation colony in Nosy Be, mainly producing sugar and cash crops. During the Russo-Japanese War Nosy Be became a supply station for Russia’s Second Pacific Squadron. The main fleet led by Admiral Zinovy Rozhestvensky reached Nosy Be on January 9, 1905, where it met a smaller detachment led by Admiral Dmitry von Fölkersam that had arrived already on December 28, 1904. The fleet stayed for two months for refurbishing and coaling, leaving on March 17 to meet its fate ten weeks later at the Battle of Tsushima.

Nosy Be is located about eight kilometers (5.0 miles) from the coast of Madagascar in the Mozambique Channel; several smaller islands are located nearby, including Nosy Komba, Nosy Mitsio, Nosy Sakatia, and Nosy Tanikely. The island’s main town is Andoany.

The volcanic island has an area of about 312 square kilometres (120 sq mi), and reaches its highest peak at Mont Lokobe at 450 metres (1,480 feet); the volcano is of Holocene origin but has not erupted in recorded history. There are eleven volcanic crater lakes on the island.

The island is known for having one of the world’s smallest frogs (Stumpffia pygmaea) and chameleon (Brookesia minima). The Lokobe Reserve is one of Madagascar’s five Strict Nature Reserves. Nosy Be is also home to a specific color of panther chameleon (Furcifer pardalis).
Recent studies indicate that adjacent waters around the channel between Nosy Be and the Madagascar host a habitat for notable number of Omura’s whale, and this has allowed researchers to conduct field studies targeting this rare, one of the least known species, for the first time.

Nosy Be has a tropical climate. It is most humid in summer (December, January, February). The Tsaratanana massif partially protects the island from the strong north-east winds affecting the region in August or during tropical depressions.