13 Introduction all the way to the Privy Council in London that the amendments were unconstitutional, and won the case, the government simply re-enacted the law and abolished the right to appeal from the Sierra Leonean courts. The distinctions were retained in the 1973 citizenship law that is still in force today. Those with Lebanese fathers were excluded from citizenship in the land of their birth and the only home they had ever had. Only in 2006 was the law reformed to end gender discrimination; but the requirement that at least one parent or grandparent had to be of ‘negro African descent’ was retained. At its most extreme, governments have simply expelled en masse those alleged to be non-citizens. The best-known case of mass expulsion in Africa is that of the Ugandan Asians driven out of the country by the government of Idi Amin. Yet many other African countries have also expelled citizens en masse, often in appalling conditions, and without any right to a hearing. Uganda itself, in a much less well-known episode that took place under President Milton Obote, displaced a large number of Banyarwanda (many of them tracing their ancestry to the Ugandan side of the border) in the early 1980s. Among the most egregious cases described in this book are the expulsion of tens of thousands of Ethiopians of Eritrean descent who had their Ethiopian nation­ ality arbitrarily cancelled and nationality documents destroyed, before their forced expulsion to Eritrea following the eruption of war between the two states in 1998 – and tens of thousands of Eritreans of Ethiopian descent subject to reciprocal expulsions in the other direction; and the expulsion of around 75,000 black Mauritanians from their country in 1989 and 1990. Numerous other countries have periodically engaged in sweeps to expel first-generation migrants. Less dramatic but more widespread is denial of citizenship rights by bureaucracy. The discretion given to administrative officials in the individual small decisions to issue identity documents or passports, accept an application for naturalization, or add someone to the electoral or the school roll means that those perceived as outsiders can be effectively excluded from the