Vergniaud, Pierre Victurnien (pyĕr vēktürnyăNˈ vĕrnyōˈ) [key], 1753–93, French revolutionary. A brilliant lawyer, he gained attention (1790) when defending peasants who had burned a castle. Elected a deputy to the legislative assembly from the Gironde, he was a leader of the Girondists and was one of the greatest orators of the French Revolution. His most noted speeches include his address (1792) in favor of beginning the war against Austria. During the trial of Louis XVI, he unwisely recommended a referendum on the punishment of the king. He led the fight against the bloc known as the Mountain and against Maximilien Robespierre. He fell with the Girondists and was guillotined.