The 1860s (pronounced "eighteen-sixties") was a decade of the Gregorian calendar that began on January 1, 1860, and ended on December 31, 1869. The decade was noted for featuring numerous major societal shifts in the Americas. In the United States, the election of abolitionist Abraham Lincoln to the presidency in 1860 led to the secession of the southern states in the form of the Confederate States of America (CSA). The resulting American Civil War (1861-1865) would be among the first industrial wars, featuring advanced technology such as steel warships and machine guns. The victory of the Union and subsequent abolition of slavery would contribute to the decline of the global slave trade. In Latin America, conflict in Mexico ensued after the French Empire installed Maximilian I as Emperor of Mexico; former President Benito Juárez would regain his position in 1867 after a power struggle. The Triple Alliance of Empire of Brazil, Argentina and Uruguay in the Paraguayan War (1864-1870) would be among the bloodiest conflicts in South American history, leading to the death of almost 60% of the Paraguayan population. The formation of the union of Austria-Hungary in 1867 and the ongoing campaign to unify Italy by Victor Emmanuel II of Sardinia-Piedmont would effect the European balance of power. The United Kingdom would continue engaging in a series of conflicts known as the New Zealand Wars with the indigenous Māori, with the New Zealand land confiscations beginning in 1863. In Asia, the Meiji Restoration of 1868 would begin the process of transforming Japan into a global imperial power. The Qing Dynasty of China would experience decline following its defeat to the British in 1860 in the Second Opium War. In 1864, the Russian Empire would embark upon the Circassian genocide in the Caucasus, leading to the deaths or expulsion of at least 75% of the Circassian people. Politics and wars Wars French occupation of Mexico (1863–1867). Replacement of President of Mexico Benito Juárez (1861–1863) at first with Juan Nepomuceno Almonte (1863–1864) and then by Emperor Maximilian of Mexico (1864–1867) with the establishment of the Second Mexican Empire. Juárez eventually manages to recover his position (1867–1872). On 18 October 1860, the first Convention of Peking formally ended the Second Opium War. The American Civil War lasted from 1861 to 1865. The Paraguayan War (1864–1870) starts in South America, with the invasion of Paraguay by the Triple Alliance (Empire of Brazil, Argentina