Daniel Clasen, in Latin Danielis Clasenius or Clasenus (1 May 1622, Lüneburg – 20 November 1678, Helmstedt), was a German political theorist, religious scholar, and classicist. His treatises, written in Latin, dealt with law, jurisprudence, religion, and politics. Clasen was one of the earliest theorists of political religion, though preceded by Tommaso Campanella (1568–1639), and argued against accommodation theory.