The British were present in Nigeria as early as the late 1700's during the transatlantic slave trade, but the British did not begin to establish colonial rule of Nigeria until1900. They were led by Fredrick Luggard. By 1906 they had control over the entire country. When this happened, ethnic minorities that had once been fragmented, especially the Igbo, now developed more concrete identities in opposition to the British. The British turned existing governments in Nigeria into puppet governments that were controlled by a British governor. Where they couldn't control existing government, the British established new governments. The puppet governments lost all traditional authority. The people of Nigeria now had no control over their own communities. This led to much unrest. While the British controlled Nigeria they made many changes to the country. They built roads and railroads and developed cities where rural villages had once been. Also the British cultivated cash crops such as palm nuts and kernels, cocoa, cotton, and peanuts. The British began to assimilate native Nigerians to European culture by creating an education system where Nigerians were given a western education. Traditional languages were replaced by English, which was now the official language of Nigeria. In 1947 the British created a constitution that allowed traditional leaders to have a larger role in government. The Nigerian elite began to form political parties that challenged British rule. The British began to give up rule of certain regions of Nigeria in 1959. Nigeria peacefully gained independence in 1960, although the changes that the British made would remain part of Nigeria long after the British left.