In 1878, Sultanate of Sulu sold the southern part of his land bounded by the Sibuco River to an Austro-Hungarian consul Baron von Overbeck, who later tried to sell the territory to the German Empire, Austria-Hungary and the Kingdom of Italy for use as a penal colony but failed, leaving Alfred Dent to manage and establish the North Borneo Provisional Association Ltd. The Provisional Association negotiated in the 1880s with the Dutch for a definition of a boundary between the area conferred by the Sultan of Sulu and the area that the Dutch claimed from Sultan of Bulungan to settle a dispute that arose from the unknown exact location of the real border between the territory that was held by the Sultanate of Sulu and the Sultanate of Bulungan. Alexander Rankin Dunlop became the first Resident for the settlement of Tawau. On 20 January 1891, a final agreement was reached on a line along 4° 10' north latitude – on the central division of the Sebatik Island. In the early 1890s, approximately 200 people lived in the Tawao settlement, mostly immigrants from Bulungan in Kalimantan, and some from Tawi-Tawi who had fled from Dutch and Spanish rule. The settlement was renamed from Tawao to Tawau. Most of those who fled from the Dutch colonisation continued trading with the Dutch. In 1893, a British vessel S.S. "Normanhurst" sailed into Tawau with a cargo to trade. In 1898, the British built a settlement which later grew rapidly when the North Borneo Chartered Company (BNBC) sponsored the migration of Chinese to Tawau.