Those states where a single party is accorded a legal or de facto monopoly of formal political activity. This may be enforced under the constitution, or it may be a consequence of denying rival parties access to the electorate, or of a failure to consult the electorate at all. Alternatively, the electorate may be selectively defined, or consultation be otherwise manipulated, so as to ensure the return of the governing party. Until recently one‐party states came under two main categories: so‐called totalitarian states, mostly but not exclusively communist and East European; and numerous Third World states where authoritarian regimes have long had recourse to a single party to control administration, mobilize support, and supervise distribution of the available patronage. With the collapse of communism, the one‐party state is now largely confined to areas of the Third World, including some former republics and autonomous territories of the Soviet Union. It is distinct from the dominant party system where, as in post‐war Italy or post‐independence India, a single party has predominated in central government, but sometimes sharing power and within an otherwise competitive party system with representative institutions. Military governments are also a distinct form of monist government; in the course of the 1990s some military regimes sought to gain a degree of legitimacy by converting themselves into party‐based government.
The one‐party state remains most entrenched in Africa, where it appeared shortly after independence and was able to draw on a legacy of autocratic colonial rule, with only a brief experience of contested elections at the very end of decolonization. In a few cases, as in former Tanganyika, effective opposition to the ruling party had disappeared even before independence. Everywhere the ruling party had very considerable advantages denied its opponents. Starting as a successful nationalist movement or front, it was able soon after independence to profit from its control of the state and the expanded patronage now readily available. It sought to secure itself in office by suppressing its opponents. Usually, elections were restricted, or closely controlled, or replaced by the occasional plebiscite. Preventive Detention Acts, an unfortunate legacy of colonial rule, were revived and used extensively. The one‐party state was presented as a means of achieving national unity, overcoming ethnic separatism, and hastening economic development and national independence. The stated justification was the need for nation‐building above the sectional appeal of tribal loyalty which would, it was claimed, undermine imported ‘Western’ liberal democratic governmental institutions. Sometimes appeal was made to supposed pre‐colonial government forms whose consultation process (analagous to the deliberations of tribal elders) was purportedly better suited to African circumstances. In most cases it was simply an adjunct of personal rule with the party confined in a strictly limited and essentially subordinate role: little more than an agency for recruitment to the government, a conduit for political patronage, and a check on the loyalty of the armed forces and the civil service.
Since 1989 the African one‐party states have been under mounting domestic and international pressure to liberalize both politically and economically. Some African states, notably Botswana and the Gambia, have had a continuous history of contested elections, which, however, did not threaten the ruling party. Others, like Senegal since the 1970s, have experimented first with limited, and then with unrestricted, party competition, but without a change of government. With the 1990s, however, entrenched one‐party regimes became vulnerable in the changing domestic and international environment. In the French‐speaking states, representative national conferences were convened with the self‐appointed task of drafting new constitutions and supervising free and open elections. By this means incumbent rulers were forced to quit in Benin, Congo, Niger, and eventually Madagascar. In Algeria the transition from a one‐party state, under the Front de Libération Nationale (National Liberation Front), was already well advanced until the military intervened to reverse the process, fearing a landslide victory by the Islamic opposition party, Front Islamique du Salut (Islamic Salvation Front). In Zimbabwe, President Robert Mugabe's unwillingness to recognize the electoral success of the Movement for Democratic Change led to a political crisis in 2008.