The Civil war was one of the most dramatic episodes in American history. It ended with the Union intact and four million enslaved black people freed. The country entered the Reconstruction era, trying to rebuild and bring former Confederate states back into the United States and to give those states civil rights. It was also one of the first conflicts to make use of industrial warfare, which relied on large numbers of men and machines.
The Civil War was the result of a fundamental divide in the United States, with northern and southern states differing socially, economically, and politically. Northerners wanted to limit the spread of slavery and some favored its abolition, while Southerners were committed to its maintenance and expansion.
Both sides mobilized on a scale never before seen in America. The Union mustered nearly 2 million military-age men, more than half of its population, while the Confederacy mustered 800,000 to 900,000 troops—only about a quarter of its population. The Union and the Confederacy used a variety of methods to convey information on the battlefield, including printed bulletins, messages carried by dogs, and drummers beating a rhythm that told soldiers when to attack or retreat.
Both national governments increased their control over the lives of their citizens in a desperate effort to mount sustained war efforts. The Union imposed new national taxes and tampered with civil liberties. The Confederacy a republic supposedly dedicated to state’s rights saw greater national government intrusions in its territory and resorted to the draft. Both national armies employed the latest military technology, from the rifle musket carried by Union infantrymen to ironclad warships. Both armies recruited soldiers from different parts of the nation and included immigrants—one in three in the Union Army, for example, was Irish. The Union Army also included significant numbers of Germans, French, Italians, and British.