SDM 2.0

Description

Much of world history has been the history of separatism. Much of that history has been violent. New nation-states often come from the violent dissolution of larger states or empires and violence has earned many nations the right to exist as sovereign entities. Indeed, most armed conflicts since the end of the Cold War have been about self-determination. A large literature in political science and economics has tried to identify the causes of secessionist war and explain the genesis of self-determination movements. However, a core limitation had been that data on self-determination movements is heavily incomplete, overrepresenting highly mobilized, violent movements. The first version of the SDM dataset provided improved data on self-determination movements (SDMs) around the world that corrects the selection bias that characterized previous efforts to code SDMs. It also included more detailed data on group attributes and state-movement interactions for a random subset of movements.

SDM 2.0 updates and extends the original dataset. SDM 2.0 identifies a total of 502 self-determination movements in 124 countries between 1945 and 2020. The new data includes time-varying information on the exact claims made by all 502 self-determination movements, their involvement in armed conflict with the state, state-movement interactions, and a range of group attributes. Via the GeoSDM extension (Germann, Puglia, and Schvitz 2025), SDM 2.0 also provides geo-spatial data identifying the territories claimed by all 502 self-determination movements, as well as data on a range of attributes of these territories, such as their size, the proximity to international land borders, and their economic value. All coding decisions are justified in an extensive set of coding notes, which is made available as part of the dataset.

SDM 2.0 will be made publicly available after the publication of the first article based on the new dataset. Please e-mail me if you would like to negotiate early access.

In the meantime, selected data can be inspected here. You can find the codebook here.

SDM 2.0 was funded by the Economic and Social Research Council (grant reference: ES/W000598/1).