We present a temporally fine-grained data set on regimes, defined as the formal and informal rules essential for selecting leaders. The data set comprises more than 2,000 regimes from 197 polities, 1789 to 2016. We highlight how the frequency of breakdowns and particular modes of breakdown have followed cyclical rather than monotonic patterns across modern history. The most common breakdown modes, overall, are coups and incumbent-guided regime transformations. Furthermore, we report robust evidence that low income, slow or negative growth, and intermediate levels of democracy predict a higher likelihood of regime breakdown. Yet, by running change-point analysis we establish that breakdown risk has cycled substantively across periods of modern history, and the aforementioned explanatory factors are more clearly related to breakdown during certain periods. When disaggregating different breakdown modes, low income is related to, for example, breakdown due to popular uprisings, whereas intermediate democracy levels clearly predict coup-induced breakdowns and incumbent-guided transitions.