The high degree of conceptual confusion in the field of territorial selfgovernance constitutes  a major obstacle to robust findings. Based on a parsimonious definition involving three individually necessary and jointly sufficient criteria (constitutional protection, territorial quality, and strength of self-rule), we develop a new typology of territorial self-governance that carves out subnational differences in kind. Empirically, we take a fresh look at territorial self-governance in more than 2200 second-level regions in 96 Western and non-Western democracies, semi-democracies, and a selection of autocratic regimes between 2000 and 2018. The TERRGO dataset introduced in this article contains over 39 000 region-year assessments. Based on the identification of eight specific types of territorial self-governance, TERRGO allows to untangle country-specific profiles. The dataset can be used to analyze changes and asymmetries of state architectures. The framework reduces the conceptual complexity and enhances our grasp on the empirical complexity of territorial state structures. You can download the dataset here.