Bertrand Barère de Vieuzac (10 September 1755 – 13 January 1841) was a French politician, journalist and notorious member of the National Convention during the French Revolution.
During the early revolution, Barère supported a constitutional monarchy under Louis XVI. Maximilien Radix de Sainte-Foix, a member of Louis' secret council, had even pointed to Barère as a trustworthy ally to the King. In 1793 however, he became a member of the Committee of Public Safety, siding with the Mountain.
On 14 July of that year, a newspaper article called him "the single most dangerous enemy of the country", noting his changes in allegiance. The article also accused Barère of being a secret royalist who had placed himself in both political camps to ensure his safety.