Karl Loewenstein devised an ontological classification of constitutions based on his study of constitutional enactment and operation. His typology, which became particularly known in Europe and Latin America, offers valuable insights into the complex interplay between political power and constitutional norms. However, it falls short in establishing a comprehensive ontology of the nature and purposes of constitutions. Loewenstein’s factually-based or sociological approach inadequately defines constitutions ontologically. His typology lacks recognition of constitutions’ normative objectives. While Loewenstein acknowledged the need for refinement of his classification, there has not been a rigorous critique and reconstruction of his classification in terms of the normative presuppositions that it entails. In the current paper, I spotlight some fundamental shortcomings and propose necessary corrections to Loewenstein’s ontological classification of constitutions. I argue that Loewenstein overlooks the intrinsic relationship between constitutional normativity and factuality. A robust ontological classification must acknowledge that constitutions are both inherently factual and normative.