There have been three waves of scholarship on military coups d’état (or simply “coups”)—the unconstitutional replacement of chief executives by military officers—since the 1960s. The first used case studies to explore why the military overthrows governments. One of its central findings was that military uprisings were an integral part of political succession in many countries. A second wave produced the “aggregate studies” that were the first to deploy cross-national databases to identify the measurable features that distinguished more from less coup-prone political systems. These studies revealed, among other things, that coups proliferated in places with a history of instability. The third and current wave of scholarship takes advantage of the development of statistical software for limited dependent variables—then unavailable, now commonplace—to recast the quantitative research on coups. Two core findings have survived disconfirmation since the start of the third wave. First, higher income countries have fewer coups, though the effects are small (and become even weaker when models only contain developing countries). Second, “political legacy effects” mean that the probability of a coup declines with time since the last military uprising. Much of the latest wave of research pinpoints factors—like coup proofing, less inequality, or the end of the Cold War—that reduce the probability of a coup. The development of ever more sophisticated statistical techniques to divine the causes of instability, nevertheless, relies on off-the-shelf data sets and coup catalogs whose validity—properly understood as accuracy—is questionable. Only a greater attention to accuracy and complementary methods promise to produce a comprehensive account of why the military topples governments in some, but not in other, places.
Political party systems are an important element of political systems in Africa and elsewhere. They form the central intermediate institution between the general population and the government. Party systems represent and aggregate diverse political views and group interests, and they form coalitions that then form governments with potentially important consequences of democracy and political stability. Unlike the case in the period directly after independence, African party systems have been overwhelmingly multiparty since the 1990s. As a result, the literature has grown significantly, although most works focus on political parties rather than party systems. Many efforts have been devoted to classification, referring to the legal context as well as, more specifically, the number of relevant parties, the levels of institutionalization, and, less often, the degree of ideological or other polarization. While levels of institutionalization and ideological differences are generally not pronounced, more than half of African party systems have been one-party dominant, of which most are authoritarian. In contrast, two-party and pluralist-party systems, which make up approximately one half of all multiparty systems, are generally more democratic. Besides determining classifications, most analytical work focuses on the determinants of African party systems using quantitative and qualitative as well as macro- and micro-level methodologies. Three determinants are debated: first, ethnicity, which has been cited as the main social cleavage behind African party systems; however, while ethnicity matters, its effects vary and are limited; second, political institutions, especially electoral systems for legislative elections, which only partly explain fragmentation or other features; third, the performance of political parties and rationalist approaches. Scholars largely agree that all of these elements need to be taken into account. While certain functions of party systems may facilitate democratization and political stability or other outcomes, little empirical work exists on the consequences of party systems. Some evidence suggests that highly institutionalized, moderately fragmented, and polarized systems promote democracy. Future research faces many challenges, in particular the development of integrated theory and more fine-grained data, as well as an increased focus on the consequences of party systems.