In France in 1852, voters were asked whether they approved of the re-establishment of the Empire in the person of Louis Napoléon Bonaparte,  the only president of what republic?
Napoleon III Louis-Napoléon Bonaparte (born Charles-Louis Napoléon Bonaparte; 20 April 1808 – 9 January 1873) was the President of France from 1848 to 1852 and, as Napoleon III, the Emperor of the French from 1852 to 1870. He was the only president of the French Second Republic and the head of the Second French Empire.
Treaty of Campo Formio The Treaty of Campo Formio (today Campoformido) was signed on 18 October 1797 (27 Vendémiaire VI) by Napoleon Bonaparte and Count Philipp von Cobenzl as representatives of the French Republic and the Austrian monarchy, respectively. The treaty followed the armistice of Leoben (18 April 1797), which had been forced on the Habsburgs by Napoleon's victorious campaign in Italy. It definitively ended the War of the First Coalition and left Great Britain fighting alone against revolutionary France.