Historic recurrence is the repetition of similar events in history. The concept of historic recurrence has variously been applied to the overall history of the world (e.g., to the rises and falls of empires), to repetitive patterns in the history of a given polity, and to any two specific events which bear a striking similarity. Hypothetically, in the extreme, the concept of historic recurrence assumes the form of the Doctrine of Eternal Recurrence, which has been written about in various forms since antiquity and was described in the 19th century by Heinrich Heine and Friedrich Nietzsche.