Germany began to establish roots in Cameroon in 1868 when the Woermann Company of Hamburg built a warehouse. It was built on the estuary of the Wouri River. Later Gustav Nachtigal made a treaty with one of the local kings to annex the region for the German emperor. The German Empire claimed the territory as the colony of Kamerun in 1884 and began a steady push inland. The Germans ran into resistance with the native people who did not want the Germans to establish themselves on this land. Under the influence of Germany, commercial companies were left to regulate local administrations. These concessions used forced labour of the Africans to make a profit. The labour was used on banana, rubber, palm oil, and cocoa plantations. They initiated projects to improve the colony's infrastructure, relying on a harsh system of forced labour, which was much criticised by the other colonial powers.