Is Switzerland an imperialist country? The historiographical debate surrounding Swiss imperialism has centred on the character of Swiss private economic engagement in the Third World and its interplay with the Swiss federal state. The Swiss firm Alusuisse was one of the most powerful players in the international aluminium market in the 20th century. Alusuisse engaged in bauxite mining in Guinea and Sierra Leone from the 1960s onwards. This thesis examines whether Alusuisse’s actions in West Africa between 1960 and 1992 were imperialistic and whether the company collaborated with the Swiss state to achieve its aims. Two Alusuisse bauxite mining subsidiaries are investigated using the framework of investment imperialism: SIEROMCO in Sierra Leone (1960-1991) and SOMIGA in Guinea (1970-1978). A particular focus was laid on the country-company negotiations with the host governments.

Based on the company’s historical records contained in the Swiss economic archive, the thesis asserts that Alusuisse’s activities in West Africa were a case of investment imperialism. In Sierra Leone, the government granted the Swiss company a monopoly on bauxite mining. For three decades, Alusuisse extracted cheap, highquality bauxite while obscuring the profitability of its subsidiary SIEROMCO to avoid paying taxes. In Guinea, Alusuisse negotiated favourable contract conditions for bauxite mining but failed to realise their original aims due to turbulence in the global aluminium market in the 1970s. Whenever conflicts between Alusuisse and the governments of Sierra Leone and Guinea arose, the company managed to impose its priorities. This was possible due to Alusuisse’s economic power, derived from its control over capital, technical expertise, and the aluminium production process. The Swiss federal state only played a marginal role in Alusuisse’s success in West Africa. Therefore, the case of Alusuisse in West Africa supports the characterisation of Swiss imperialism as predominantly driven by private enterprises.