A state or a period of time marked by violence often committed by those in power that produces widespread terror
Any period of brutal suppression resembling the French Reign of Terror.

Period of the French Revolution when the Jacobins were in power (Oct 1793–July 1794) under Robespierre and instituted mass persecution of their opponents. About 1,400 were executed, mainly by guillotine, until public indignation rose and Robespierre was overthrown in July 1794.The historic period (1793-94) during the French Revolution when thousands were executed.