7 Introduction some countries (Uganda and the Democratic Republic of Congo) the constitution itself still limits those who may be citizens by birth to the ethnic groups present in the country on a particular date, with many arguments about what that date should be; in others (Sierra Leone and Liberia) only those ‘of negro descent’ can be full citizens; in yet others (among them Nigeria) there is an implied preference for the native over the immigrant in citizenship laws that require descent from ancestors who were born in the country. A similar distrust was applied to those potential citizens of the new states who might have a claim on another passport; the great majority of African countries prohibited dual citizenship either at or soon after independence (though the rules have often changed in recent years). They wished to ensure that those who might have a claim on another citizenship – especially those of European, Asian or Middle Eastern descent – had to choose between their two possible loyalties. Those who did not take the citizenship of the newly independent country were then regarded with suspicion, as a possible ‘fifth column’ for the former colonial powers and other interests. Not coincidentally, these rules were most problematic in those countries where colonial-era migration and dispossession of land had been most marked, where the numbers of those who had arrived during empire remaining after independence were largest, and where the political power of those affected was weakest. As happened later following the collapse of the Soviet Union, when the European empires in Africa retreated they left behind a legacy of resentment of incomers and their privileges that still reverberates today. But the migration of the first half of the twentieth century was not only of Europeans and Asians: hundreds of thousands of Africans also moved, sometimes under duress, as a result of the political and economic changes brought by colonization. Despite the strong rhetoric of African solidarity that all governments express, these migrants also find their right to citizenship and belonging under threat today. Some of the most egregious cases of citizenship d ­ iscrimination