Sumbawa had, historically speaking, three major linguistic groups who spoke languages that were unintelligible to each other. One group centered in the western side of the island speaks Basa Semawa (Indonesian: "Bahasa Sumbawa") which is similar to the Sasak language from nearby Lombok; the second group in the east speaks Nggahi Mbojo ("Bahasa Bima"). They were once separated by the Tambora culture, which spoke a language related to neither. After the demise of Tambora due to the 1815 eruption, local kingdoms based in Sumbawa Besar and Bima became the two focal points of Sumbawa. This division of the island into two parts remains today; Sumbawa Besar and Bima are the two largest towns on the island, and are the centers of distinct cultural groups that share the island.