Magna Carta’s status as a touchstone of modern thinking about the rule of law rests on several well-known myths. This article evaluates the influence of Magna Carta on modern constitutions, both in termsof formation as well as content. The analysis confirms that Magna Carta’s relevance is, if anything, onthe rise, even if the causal chains linking it to current developments are weak-linked and distant. Wespeculate on the mysterious processes that produce influence among legal texts, arguing that championsand empire are crucial factors in the case of Magna Carta.