thumb|right|240px|The position of the Bacans in the Moluccas
The Bacan Islands (; ), formerly also known as the Bachans, Bachians, and Batchians, are a group of islands in the Moluccas in Indonesia. They are mountainous and forested, lying south of Ternate and southwest of Halmahera. The islands are administered by the South Halmahera Regency of North Maluku Province. They formerly constituted the Sultanate of Bacan.
Bacan (), formerly also known as Bachian or Batchian, is the group's largest island. Bacan Island in 2020 included about 82,387 people, of whom 7,073 lived in the capital Labuha; it is subdivided into seven districts. The second and third-largest islands are Kasiruta and Mandioli. Kasiruta and Mandioli each have over 11,000 inhabitants, and each is subdivided into two districts. A fourth island, Batang Lomang, forms a twelfth district within the group. There are dozens of smaller islands in the group, which had a total population of 84,075 at the 2010 Census, The official estimate as at mid-2023 was 117,986.
Administration
The group is divided into twelve administrative districts (kecamatan) out of the thirty districts within South Halmahera Regency. They are tabulated below with their areas and their populations at the 2010 Census and 2020 Census,
Following the 1575 Ternatan invasion, Bacan become subservient to Ternate for periods, which was sealed through marriages. A sister and a daughter of Sultan Saidi Berkat of Ternate married Bacan rulers in the late 16th and early 17th centuries. A Spanish fort was built in 1606. By this time the seat of the sultan had been moved from Kasiruta to Bacan Island. Once the Dutch East India Company established hegemony in 1609, the Netherlands' power on Bacan was based in Fort Barnaveld. The chief town at the time, also known as Bachian, was Amasing or Amasingkota on the island's isthmus.
Ternate and Bacan were the only places in the northern Moluccas that had a Dutch curriculum school and a Protestant minister in the late 19th century. The majority of Bacan's Roman Catholics became Protestants during the Dutch colonial period. These Sirani wore semi-European dress and celebrated Sundays with dancing and music. The was treated as a Dutch protectorate; it was replaced by a council of chiefs under a Dutch ' in 1889. A sultan with much reduced powers was eventually appointed in 1900. What independence remained was lost with the Japanese occupation during and Indonesian independence after World War II. The whole group had a population of 84,075 at the 2010 Census, but by mid 2023 had grown to 117,986.
Several non-Austronesian (Papuan) languages are spoken on Bacan, the main one of which is Galela but also Tobelo and Ternate. Near the capital Labuha, Bacan Malay was once spoken by the Bacan people, but by 2012 only a handful of speakers remained.
Economy
Colonial interest in Bacan was primarily driven by the spice trade, which was flourishing in Ternate, Tidore, and Halmahera. The island of Bacan was not particularly sought after for its own resources, but rather, to assist control of the more valuable islands nearby. The Dutch East India Company paid a stipend to the Bacan sultan as compensation for the destruction of Bacan's clove trees that was higher than the salary of the Dutch Governor on Ternate and about 1/9 of that paid to the Sultan of Ternate.
It is thought that gold was washed on Bacan since at least 1774; in the mid-nineteenth century, 20 skilled Chinese gold workers were brought from west Borneo but a gold rush did not eventuate. During the era of steam power, an attempt was made to establish coal mining on the island using Japanese convicts imprisoned by the Dutch. However, following the delivery of several tons the grade of coal was deemed poor and the mining was discontinued.
From 1882, an Amsterdam merchant cleared plantations for vanilla, coffee, tobacco and potatoes, however, his land was unsuitable and the crops succumbed to floods, drought, rot, insects and rodents. Despite over ten years of large investments of capital, creditors forced him out of business in 1900 although they also did not succeed with the plantations.