‘What is diaspora?’ attempts to define this wide-ranging — but often inappropriately used — term. Diaspora is more than simply migration. It is an idea which helps to explain the world created by migration. The term originates from Ancient Greek, where it had negative connotations. This became applied to Judaism when Greek scholars translated the Penteteuch — Jewish cultural history is highly diasporic. The term expanded to include the Armenian and African diasporas, but since the 1980s it has ballooned even further. If overused, the term can become arbitrary, so it is best applied to groups which have migrated involuntarily, which maintain an interest in their homeland, and have multiple groups worldwide.