In the course of civil war, it is not unusual for armed rebels, who are fighting to either take control of a state or create a new one, to create state-like governing institutions. For example, nearly 64% of rebels between 1945 and 2012 created at least one governing institution. One challenge to moving the literature on rebel governance forward is getting data on the many possible institutions that comprise rebel governance. I introduce new data, the Rebel Quasi-State Institutions dataset, which covers 235 rebel groups and codes annually for 25 institutions during the entire existence of the group. I demonstrate the usefulness of this new dataset by exploring a relationship important to scholars: that of rebel strength and rebel governance institutions ( Stewart, 2020 ). These analyses show two things. First, there is value in disaggregating rebel governance and looking at institutions separately because not all governance institutions are correlated with strength in the same direction. Second, taking into account the time dimension is important. Since rebel conventional capability increased as a result of the end of the Cold War (Kalyvas & Balcells, 2010) and rebel institutions became more prevalent, there is an important time component to rebel governance that correlates with events in the international system.