For many Americans, Memorial Day is more than a long weekend and an unofficial start to the summer season. The real meaning of the holiday is meant to honor all U.S. soldiers who have died serving their country.

Originally called Decoration Day, Memorial Day's history goes back to the Civil War. It was was declared a national holiday by Congress in 1971, according to the U.S. Department of Veterans' Affairs.

Although Veterans Day in November also honors military service members, Memorial Day differs by honoring all military members who have died while serving in U.S. forces in any current or previous wars.

The late-May holiday has also evolved into an opportunity for Americans to head to the beach or lake, travel to see friends and family, or even catch a Memorial Day parade.

Here's what to know about the history and the reason behind why we observe Memorial Day.

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When is Memorial Day?

One of 11 federal holidays recognized in the U.S., Memorial Day is always observed on the last Monday of May. This year, the holiday falls on Monday, May 27.

Why do we celebrate Memorial Day?  

The origins of the holiday can be traced back to local observances for soldiers with neglected gravesites during the Civil War.

The first observance of what would become Memorial Day, some historians think, took place in Charleston, South Carolina at the site of a horse racing track that Confederates had turned into a prison holding Union prisoners. Blacks in the city organized a burial of deceased Union prisoners and built a fence around the site, Yale historian David Blight wrote in The New York Times in 2011.

Then on May 1, 1865, they held an event there including a parade – Blacks who fought in the Civil War participated – spiritual readings and songs, and picnicking. A commemorative marker was erected there in 2010.

One of the first Decoration Days was held in Columbus, Mississippi, on April 25, 1866 by women who decorated graves of Confederate soldiers who perished in the battle at Shiloh with flowers. On May 5, 1868, three years after the end of the Civil War, the tradition of placing flowers on veterans’ graves was continued by the establishment of Decoration Day by an organization of Union veterans, the Grand Army of the Republic. 

General Ulysses S. Grant presided over the first large observance, a crowd of about 5,000 people, at Arlington National Cemetery in Virginia on May 30, 1873.

This tradition continues to thrive in cemeteries of all sizes across the country. 

Until World War I, Civil War soldiers were solely honored on this holiday. Now, all Americans who’ve served are observed. 

At least 25 places in the North and the South claim to be the birthplace of Memorial Day. Some states that claim ownership of the origins include Illinois, Georgia, Virginia, and Pennsylvania, according to Veterans Affairs.

Despite conflicting claims, the U.S. Congress and President Lyndon Johnson declared Waterloo, New York, as the “birthplace” of Memorial Day on May 30, 1966, after Governor Nelson Rockefeller's declaration that same year. The New York community formally honored local veterans May 5, 1866 by closing businesses and lowering flags at half-staff. 

Why is Memorial Day in May? 

The day that we celebrate Memorial Day is believed to be influenced by Illinois U.S. Representative John A. Logan, who was elected to the U.S. House of Representatives as a Democrat in November 1858, and served as an officer during the Mexican War.

It is said that Logan, a staunch defender of the Union, believed Memorial Day should occur when flowers are in full bloom across the country, according to the National Museum of the U.S. Army.

Congress passed an act making May 30 a holiday in the District of Columbia in 1888, according to the U.S. Congressional Research Service.

In 2000, the National Moment of Remembrance Act – which created the White House Commission on the National Moment of Remembrance and encourages all to pause at 3 p.m. local time on Memorial Day for a minute of silence – was signed into law by Congress and the President.

What is the difference between Memorial Day and Veterans Day?

Memorial Day and Veterans Day both honor the sacrifices made by U.S. veterans, but the holidays serve different purposes.

Veterans Day, originally called “Armistice Day,” is a younger holiday established in 1926 as a way to commemorate all those who had served in the U.S. armed forces during World War I.

Memorial Day honors all those who have died.