Ideas about states of emergency went back to the politics of Ancient Rome in which it was said that ‘necessity knows no law’. This idea took on a series of different meanings during the early modern period and was employed by the Jacobins during the invasion scare of 1793–94. In 1848 the idea was employed again to justify emergency rule after the June uprising in Paris, but in its later usages, particularly by Marx, the idea was inverted. It was no longer emergency that justified dictatorship. Rather, dictatorship was posited as a desirable outcome in a transition to new forms of society.