The first permanent state in present-day Ghana was the Bono state of the 11th century. Numerous kingdoms and empires emerged over the centuries, of which the most powerful were the Kingdom of Dagbon in the north and the Ashanti Empire in the south. Beginning in the 15th century, the Portuguese Empire, followed by numerous other European powers, contested the area for trading rights, until the British ultimately established control of the coast by the late 19th century. Following over a century of native resistance, Ghana's current borders took shape, encompassing four separate British colonial territories: Gold Coast, Ashanti, the Northern Territories and British Togoland. These were unified as an independent dominion within the Commonwealth of Nations on 6 March 1957, becoming the first colony in sub-Saharan Africa to achieve sovereignty. Ghana subsequently became influential in decolonisation efforts and the Pan-African movement.