Seibert has visited São Tomé and Príncipe regularly since 1989. In the 1990s he spent there several longer periods lasting between two and nine months, conducting social science research for his PhD thesis, “Comrades, Clients and Cousins. Colonialism, Socialism and Democratization in São Tomé and Príncipe”. During his consecutive stays in the archipelago, he has become familiar with different sectors of the local society including journalists, civil servants, and members of the local political elite from several parties (MLSTP/PSD, PCD, MDFM, ADI). He knows the president and his two predecessors, as well as several former and current members of government. Seibert authored the São Tomé and Príncipe chapter in Africa South of the Sahara (London: Routledge).