Kalimantan is a province under the Republic of Indonesia.  It occupies most of the central and southern parts of Borneo and is the largest region in the island of Borneo.   Kalimanatan was under the Dutch colonial prior to its independence.  Before that,  parts of Kalimanatan was once ruled by the powerful Banjarmasin (most notably in Central Kalimantan) which was an Islam sultanate in the 17th century, as well as the Brunei Sultanate.  After the end of the Japanese occupation, Kalimantan was automatically controlled by the locals and directly proclaimed under the Republic of Indonesia on 17 August 1945.