An ambulance crew demonstrates the removal of wounded soldiers from the field during the Civil War. — Library of Congress

En español | Echoes of the nation’s greatest fight — the Civil War — still reverberate from coast to coast.

See also: Civil War Trivia Quiz

Some ring strong: of course the end of slavery, perhaps the worst disgrace in the nation's history. And the 620,000 ancestors lost. Other vestiges have weakened with the passage of time but are no less legacies of the four horrific, heroic years that shaped us as one nation.

Here are eight ways the Civil War indelibly changed us and how we live:

1. We have ambulances and hospitals.

The Civil War began during medieval medicine's last gasp and ended at the dawn of modern medicine. Each side entered the war with puny squads of physicians trained by textbook, if at all. Four years later, legions of field-tested doctors, well-versed in anatomy, anesthesia and surgical practice, were poised to make great medical leaps.

The nation's first ambulance corps, organized to rush wounded soldiers to battlefront hospitals and using wagons developed and deployed for that purpose, was created during the Civil War. The idea was to collect wounded soldiers from the field, take them to a dressing station and then transport them to the field hospital.

Doctors laid out the hospitals as camps divided into well-defined wards for specific activities such as surgery and convalescence. Women flocked to serve these hospitals as nurses.

Before the war, most people received health care at home. After the war, hospitals adapted from the battlefront model cropped up all over the country. The ambulance and nurses' corps became fixtures, with the Civil War's most famous nurse, Clara Barton, going on to establish the American Red Cross. Today's modern hospital is a direct descendant of these first medical centers.

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