Measured in physical devastation and human lives, the American Civil War was the costliest war in the experience of the American people. When the war ended, 620,000 men (in a nation of 35 million people) had been killed and at least that many more had been wounded. The North lost a total of 364,000 (nearly one of every five Union soldiers) and the South 258,000 (nearly one of every four Confederate soldiers). More men died of disease and sickness than on the battlefield; the ratio was about four to one.

The physical devastation was largely limited to the South, where almost all the fighting took place. Large sections of Richmond, Charleston, Atlanta, Mobile, and Vicksburg lay in ruins. The countryside through which the contending armies had passed was littered with gutted plantation houses and barns, burned bridges, and uprooted railroad lines. Many crops were destroyed or confiscated, and much livestock was slain. More than $4 billion worth of property had been wiped out through emancipation, the repudiation of Confederate bonds and currency, the confiscation of cotton, and war damage.

The war settled the question of the permanence of the Union; the doctrine of secession was discredited, and after 1865 states would find other ways to manifest their grievances. The war expanded the authority of the federal government, with the executive branch in particular exercising broader jurisdiction and powers than at any previous time in the nation’s history. The U.S. Congress, meanwhile, enacted much of the legislation to which the South had objected so strenuously before the war, including a homestead act, liberal appropriations for internal improvements, and the highest tariff duties in American history to that date. Economically, the war encouraged the mechanization of production and the accumulation of capital in the North. The needs of the armies in the field resulted in the mass production of processed foods, ready-made clothing, and shoes, and after the war, industry converted such production to civilian use. By 1865 the U.S. was on its way to becoming an industrial power.

Finally, the American Civil War brought freedom to nearly 4 million blacks. But the attitudes that had sustained slavery in the South for more than 300 years did not end with the war, thereby creating tensions and problems that would persist into the 20th century.

Excerpted from the History Channel