This article aims to review the available sources and all the subsequent scholarship on the long-discussed offer made to the Czech pedagogical reformer and philosopher Comenius (1592-1670) to preside over Harvard University in 1642. Since all information is only based on the American writer Cotton Mather (1663-1728) mourning Comenius' refusal to move to the New World, we proceed to analyze supporting evidence -mainly letters- of various people involved in the alleged plot, such as John Winthrop Jr., governor of Connecticut, Hartlib, the English publisher, or Comenius himself, and consider the truthfulness of Cotton Mather's statements, the only source in the entire story.