The discredited Bourbon dynasty was overthrown by the July Revolution of 1830, which established the constitutional July Monarchy. In that year, French troops conquered Algeria, establishing the first colonial presence in Africa since Napoleon's abortive invasion of Egypt in 1798. In 1848, general unrest led to the February Revolution and the end of the July Monarchy. The abolition of slavery and introduction of male universal suffrage, which were briefly enacted during the French Revolution, were re-enacted in 1848. In 1852, the president of the French Republic, Louis-Napoléon Bonaparte, Napoleon I's nephew, was proclaimed emperor of the Second Empire, as Napoleon III. He multiplied French interventions abroad, especially in Crimea, in Mexico and Italy which resulted in the annexation of the Duchy of Savoy and the County of Nice, then part of the Kingdom of Sardinia. Napoleon III was unseated following defeat in the Franco-Prussian War of 1870 and his regime was replaced by the Third Republic. By 1875, the French conquest of Algeria was complete and approximately 825,000 Algerians were killed as a result.