160 years ago today, on April 9, 1865 (March 14, 1865), the American Civil War ended. After the American Revolution in the 18th century, a federal system was established, and the bourgeoisie and plantation slaveholders jointly ruled. However, the North and the South still went their separate ways: the American South developed black slavery on the basis of plantation economy, and the North developed capitalist employment. By the mid-19th century, the contradiction between these two opposing social systems had developed to the point of irreconcilability. Southern slavery became the main obstacle in the American social economy. In 1860, Lincoln, who was famous for calling for the maintenance of federal unity and opposing the expansion of slavery, was elected the 16th President of the United States. Feeling that power was being sidelined, southern slaveholders began to create divisions and deliberately launched a rebellion. In early 1861, the "Union of Southern States" was established in the South. On April 12, southern rebels shelled Fort Sumter, where the Union troops were stationed, openly provoking civil war. On April 15, Lincoln was forced to declare the South a rebel state and conscripted 75,000 volunteers to fight for the restoration of federal unity. By contrast, the North had an absolute advantage in terms of state number, population, industrial production, finance, transportation, military power, and political support. However, the Union army was frequently defeated in the early days of the war. This was because the Confederate army was well-prepared to seize the initiative, but also because the Lincoln government put aside the most sensitive issue of slavery. In July 1861, the first battle in Manassas City, 40 kilometers away from Washington, was defeated by the small Confederate army, and Washington was almost lost. After that, the masses held demonstrations to demand the liberation of slaves, the distribution of peasant land, and the rescue of the dangerous situation. In order to change this situation, the Lincoln government took two major reform measures in time. On May 20, 1862, the government promulgated the Homestead Law, and on September 22, the Emancipation Proclamation was issued. After this, the situation of the war changed fundamentally, and the Union army gradually took the initiative in each battlefield. In the summer of 1863, the Union army turned to a counteroffensive. After the decisive victory at Gettysburg on July 1-3, the Union army captured Vicksburg on the lower Mississippi River on July 4, destroying the Allied offensive force and completely turning the tide of the war. Then, the Union army adopted a new strategy to actively attack, and by the end of 1864, the South was almost paralyzed. In November 1864, Lincoln was re-elected president with an overwhelming majority, and the defeat of the South was certain. On April 3, 1865, the Union army captured Richmond. On April 9, General Robert Lee, the commander-in-chief of the Confederate army, led 28,000 men to surrender to the Union Army. The American Civil War ended with the victory of the North and the United States was restored. The American Civil War was the second bourgeois revolution in American history, which shattered the greatest obstacle to American political and social development - slavery, thus enabling the United States to prosper in the shortest possible time and become the largest capitalist country.