Associated Press

Monday, hundreds of thousands of Americans all over the world will pause to remember those who have died in American wars. It's a tradition that began in 1868 and continues with Memorial Day observances today.

The National Moment of Remembrance encourages all Americans to pause at 3 p.m. local time for a minute of silence.

Here's a look at observances of Memorial Day throughout its long history, from back in the 1800s when it was known as "Decoration Day" to the present.

>> An American flag is reflected against the names on the Vietnam Veterans Memorial during Memorial Day ceremonies Monday, May 25, 1998 in Washington.

1868
Library of Congress

This stereograph shows President Grant and General John Logan seated at a flag-draped reviewing stand during the first official Decoration Day (later renamed Memorial Day) at Arlington Cemetery in 1868.

1876
Library of Congress

This stereograph showing a crowd gathered in front of a statue of Abraham Lincoln in Union Square Park, which has been decorated for Memorial Day in 1876.

1876
Library of Congress

Orphans decorate their fathers' graves in the Glenwood Cemetery, Philadelphia, on Decoration Day in 1876.

1884
Library of Congress

The halt of the Grenadiers Rochambeau in Union Square New York is shown on Decoration Day, May 30, 1884.

1899
Library of Congress

Girls pose with daisies gathered for Decoration Day, May 30, 1899.

1900
Library of Congress

People place garlands of flowers on graves on Decoration Day, in Manila, 1900.

1903
Utah State Historical Society

This photo shows soldiers marching down Main Street in Salt Lake City during the May 30, 1903, Decoration Day parade.

1907
Utah State Historical Society

This 1907 photo shows Salt Lake City's Decoration Day Parade down Main Street on May 30, 1907.

1907
Utah State Historical Society

A group of Fort Douglas soldiers march in a Decoration Day parade in Salt Lake City, May 30, 1907.

Between 1909 and 1912
Library of Congress

President William Taft reviews a parade with Capt. Archie Butt at his side in this undated Decoration Day photo.

1911
Utah State Historical Society

This 1911 photo shows a group of men, women and children gathered at the Salt Lake City Cemetery for Memorial Day service.

1911
Utah State Historical Society

This 1911 photo shows a group of men gathered around a monument at the Mount Olivet Cemetery during a Memorial Day service.

1912
Library of Congress

Twenty-one members of the Mullan Fire Department in Idaho pose holding flowers on Decoration Day, 1912.

1917
Library of Congress

This photo shows a Decoration Day, parade in 1917.

1917
Library of Congress

This photo shows a Decoration Day parade in 1917.

1917
Library of Congress

This photo shows men marching in a Decoration Day parade in 1917.

1935
Library of Congress

The American Memorial Day is observed in Brookwood cemetery, London, England on June 5, 1935, with services conducted by the Reverend Money. Many prominent people placed wreaths upon the memorial flagstaff. The photo shows Robert Frazer, the American consul-general in London, as he placed a wreath in position.

1943
Library of Congress

At Memorial Day exercises in a New Guinea military cemetery on May 30, 1943, a wreath is placed on the grave of Byron Darnton, New York Times war correspondent killed on October 18, 1942 in line of duty. Left to right around Brig. Gen. Hanford MacNider (kneeling in center): Willard Hahn, INS; Robert Cromie, Chicago Tribune; Murlin Spencer, AP; Dean Schedler, AP; Jack Turcott, New York Daily News; Charles Rawlings, Saturday Evening Post; and Larry Meier, Look Magazine.

1943
Library of Congress

A U.S. Honor Guard fires a volley over the graves of fallen comrades in the first Memorial Day services held at El Alia Cemetery near Algiers, North Africa on May 30, 1943.

1943
Library of Congress

A school band plays at Decoration Day ceremonies in Gallipolis, Ohio, in June 1943.

1943
Library of Congress

This photo shows a grave decorated on Decoration Day, 1943.

1943
Library of Congress

Girl flag bearers appear at the Decoration Day ceremonies in Gallipolis, Ohio, 1943.

1943
Library of Congress

A soldier salutes at Decoration Day ceremonies in Gallipolis, Ohio, in 1943.

1945
Associated Press

American soldiers look for the graves of friends following Memorial Day rites in Brookwood cemetery in Surrey, South of London, England, May 30, 1945. Two crosses in foreground bear names William John Clark, Lt. (JG) U.S.N., left, and Leon C. Hattaway, machinist mate 1ts class, U.S.N., right.

1946
Associated Press

Throughout the Mediterranean Theatre of Operations, at each of some 60 American and British cemeteries, Allied soldiers and civilians paid respects to their dead in Memorial Day services. At the Nettuno Cemetery on the Anzio Beachhead, Lieutenant General John C. H. Lee, Theater Commander told an Allied throng that the men buried there were "becoming the seed of the United Nations Organization "Where," he said, "are not only the remains of our American heroes, but those of our gallant allies." Photo shows a general view of the Nettuno Cemetery during Memorial Day ceremonies, May 30, 1946, after wreaths had been placed near the base of the flag.

1947
Associated Press

Mr. and Mrs. G.K. Cousins of Dagenham, Essex England place flowers on the grave of Edwin E. Gilson, an American soldier from Boston buried in the British Isles, during American Memorial Day service in Britain on June 1, 1947.

1947
Associated Press

A small boy's grave on a South Dakota prairie, near the town of Elrad, is the scene each Memorial Day of a ceremony which has been carried on for decades by the train crew of the Chicago and North Western Railway's Train 106. Each year the train makes an unscheduled stop to place flowers on the grave, carrying on a tradition begun in 1888 by a conductor who was a friend of the little boy. This photo is dated May 28, 1947.

1953
Associated Press

Memorial Day observance, an American tradition, will include the men of all allied nations fighting in Korea, who lie in this U.N. military cemetery at Pusan, South Korean. Flags of the United Nations wave in background on May, 29, 1953.

1960
Associated Press

Memorial Day has special meaning for all Americans — to remember, in deep sorrow and lasting affection, those who laid down their lives for their nation. Here tribute is paid in a ceremony at the United Nations Cemetery near Pusan, South Korea on May 20, 1960. An Army man, SFC Delmas Davidson of Huntington, W. Va., raises the flag while the Navy's Milo E. Golden of Wichita, Kan. blows taps.

1987
Associated Press

Alan Pitts, rear, of Graysonville, Md., and Peter Kelsch of Miami, Fla., observe the Memorial Day service at the Vietnam Veterans Memorial in Washington, May 25, 1987. The two served together in Vietnam in 1966 and 1967.

1989
Associated Press

American Gold Star mothers Eleanor Wimbish, left, of Glen Burie, Md.; Evelyn Barbour, center, of Richmond, Va.; and Winona Tucker of Jerseyville, Ill., pay their respects during the playing of "Taps" during a Memorial Day service at the Vietnam War Memorial in Washington, May 30, 1989.

1991
Associated Press

General Colin Powell, chairman of the Joint Chiefs of Staff, bows his head after laying a wreath at the annual Memorial Day observance at the Vietnam Memorial, May 27, 1991 in Washington.

1991
Associated Press

Veterans DeWayne Miller, left, and Pat McElrath, both of Seattle, embrace in front of the Vietnam Memorial at a Memorial Day observance in Washington, May 27, 1991. McElrath was wounded during the liberation of Panama in December 1989.

1992
Associated Press

Carlos Mendez, a Vietnam veteran with his 4-year-old daughter Mia, plays "Taps" on a harmonica at the Los Angeles National Cemetery, Los Angeles, Calif., May 25, 1992. The cemetery was the site of Memorial Day services.

1993
Associated Press

President Clinton, accompanied by Jan Scruggs, president , Vietnam Memorial Fund, pauses at the Vietnam Veterans Memorial after giving a Memorial Day speech Monday, May 31, 1993.

1993
Associated Press

A saluting Marine is reflected in the Vietnam Veterans Memorial in Washington, D.C., Memorial Day, May 31, 1993. U.S. President Bill Clinton will give a Memorial Day speech at the memorial.

1996
Associated Press

An unidentified veteran of the U.S. armed forces plants a flag at the grave of a comrade at the Long Island National Cemetery in East Farmingdale, N.Y., Saturday, May 25, 1996.

1996
Associated Press

One of thousands of visitors to the Vietnam Veterans Memorial in Washington pauses for a solemn, private moment Memorial Day, Monday, May 27, 1996. The individual is not identified.

1996
Associated Press

An unidentified woman grieves at the grave of a U.S. soldier at the Long Island National Cemetery in East Farmingdale, N.Y., Saturday, May 25, 1996. The woman was among hundreds who planted flags at all the graves. The cemetery is the largest of the nation's 114 federal cemeteries, with 319,000 bodies interred.

1996
Associated Press

Jane McGuire takes a rubbing of her brother's name off of the Vietnam Veterans Memorial wall, currently on display at Green Hill Memorial Park in Rancho Palos Verdes, Calif., May 26, 1996. The wall is a traveling replica of the nation’s Vietnam Veterans Memorial wall in Washington, D.C. The replica, listing 58,196 Americans who died or are missing in action in the war, gave Californians who may never make it to Washington a chance to remember those who died.

1996
Associated Press

United States Korean War veterans William Smalling, left, and Frank Vellia, right, salute the grave of a U.S. armed forces veteran at the Long Island National Cemetery in East Farmingdale, N.Y., Saturday, May 25, 1996. Both veterans are members of VFW Post 2770 in Bellmore, N.Y., as was the deceased soldier.

1996
Associated Press

The Duhame family, from left, nine-year-old Zack, Doc, Cynthia and six-year-old Rachel, visit the Los Angeles National Cemetery, May 26, 1996. Although the family has no relatives buried in the cemetery, their visit is a lesson on the meanoing of Memorial Day.

1996
Associated Press

Roni DeJoseph, of the Brooklyn borough of New York, who identified himself as a U.S. Marine veteran who fought in Vietnam, pays honor to a friend as he visits the Vietnam Wall Experience, a traveling replica of Washington Vietnam Veteran's Memorial Wall, following Brooklyn's 129th consecutive Memorial Day Parade in New York Monday, May 27, 1996.

1997
Associated Press

Active duty military personnel and veterans unfurl a giant American flag on the deck of the aircraft carrier Intrepid on Memorial Day, Monday, May 26, 1997, as part of New York City's Fleet Week activities. The carrier is now a floating air and space museum on the city's waterfront.

1997
Associated Press

Soldiers of the 229th Attack Helicopter Regiment of the U.S. Army deployed in Bosnia as part of the NATO led peace force are attending the Memorial day ceremony at the U.S. Army camp Comanche near Tuzla on Monday, May, 26, 1997.

1997
Associated Press

Seven-year-old Stacey Hargrave of San Pedro, Calif., holds an American flag that toppled over due to wind at the Los Angeles National Cemetery Sunday, May 25, 1997, in Los Angeles. After pausing for a moment, she stuck the flag back into the ground. Hargrave was visiting the graves of her great-grandparents with her family.

1998
Associated Press

An American flag waves at a gravesite at Arlington National Cemetery in Arlington, Va. Thursday May 21, 1998 to honor America's fallen heroes for Memorial Day. The tradition, known as "flags in," has been conducted anually since the 3rd Infantry, The Old Guard, was designated as the Army's official ceremonial unit in 1948.

1998
Associated Press

A man and a girl eye the statue of a Civil War-era soldier that stands over thousands of graves of U.S. military veterans in preparation for Memorial Day ceremonies at Los Angeles National Cemetery in the Westwood district of Los Angles, Sunday, May 24, 1998. Memorial Day will be observed on Monday, May 25.

1999
Associated Press

The three-arch stone gate that greets visitors to Crown Hill Cemetery in Indianapolis, is shrouded in fog Sunday, May 23, 1999, as a flag hung for Memorial Day hangs from the center archway. Crown Hill is the final resting place for more than 190,000 people from pioneers to presidents.

1999
Associated Press

Samuel B. Mullin, of Boston, a 65-year-old U.S. Army veteran of both the Vietnam and Korean Wars, looks out over the graves of thousands of veterans at the Mount Hope Cemetery in Boston, Sunday, May 30, 1999. Mullin visited the grave of his brother James W. Mullin on Sunday, who was wounded but was not killed during the Dec. 7, 1941 Japanese air attack on Pearl Harbor.

2000
Associated Press

The early morning sun silhouettes the Iwo Jima Memorial Thursday May 25, 2000, as the Washington D.C. area gets ready for the Memorial Day Weekend. Washington will celebrate the holiday with various events around the city.

2000
Associated Press

A Civil War era military statue keeps watch over graves at the Golden Gate National Cemetery Friday, May 26, 2000, in San Francisco. Flags are flying in preparation for Memorial Day on Monday.

2000
Associated Press

Officials and servicemembers lay floral tributes at the annual Memorial Day service at the Cambridge American Cemetery, in Madingley, central England Monday, May 29, 2000. The cemetery contains the graves of 3,000 American servicemen and women killed in World War Two and a Wall of Missing which lists over 5,000 names of those missing in action.

2001
Associated Press

Sgt. Jerry Surber, of Jackson, Mich., and a member of the The Old Guard, 3rd US Infantry, takes part in the traditional Memorial Day, "Flags In", the placing of the American flags at the gravestones of service members buried at Arlington Cemetery in Arlington, Va., Thursday, May 24, 2001.

2001
Associated Press

President Bush walks with Maj. Gen. James T. Jackson, center, at a wreath-laying ceremony at the Tomb of the Unknowns at Arlington National Cemetery in Arlington, Va., Monday, May 28, 2001. Others in photo are unidentified.

2002
Associated Press

U.S.and Canadian troops salute to soldiers who died since Operation Enduring Freedom was launched on Monday May 27, 2002 at Kandahar Airport, Afghanistan. The Memorial Day service dedicated to the 47 U.S. troops and four Canadian soldiers killed since the start of the American-backed campaign started last November. Of the total, 37 U.S. troops died in Afghanistan and four in the Philippines.

2002
Associated Press

Fog shrouds the grave of Revolutionary War soldier Obed Aaron in a grave yard in Hilltown, Pa., Sunday, May 26, 2002. Memorial Day will be celebrated Monday.

2002
Associated Press

U.S. Army honor guard, top, and U.S. Air Force honor guard, bottom, march side by side during a Memorial Day ceremony at the Tomb of the Unknowns at Arlington National Cemetery in Arlington, Va., Monday, May 27, 2002.

2002
Associated Press

One-year-old Elleanor Payette, stands next to a grave marker while visiting the Los Angeles National Cemetery with her family during Memorial Day Monday, May 27, 2002, in Los Angeles.

2002
Associated Press

With the New York City skyline as a backdrop,100 ft. U.S. flag is held by active members and veterans of all five armed sevices during the Memorial Day commemoration ceremony aboard the Intrepid Sea Air Space Museum, Monday, May, 27, 2002 in New York.

2003
Associated Press

The gravestone of Civil War officer Rueben Hunter stands in the Boalsburg Cemetery in Boalsburg, Pa., Saturday, May 10, 2003. Emma Hunter and two other Boalsburg women went to the village cemetery in 1864 to lay flowers and ferns on graves in what locals now call the nation's first Memorial Day observance. Some two dozen communities across the U.S., including Boalsburg, now claim to be the birthplace of Memorial Day. The official distinction, signed into law by PresidentJohnson in 1966, is held by the village of Waterloo, N.Y.

2003
Associated Press

Bikers pass the Lincoln Memorial as they arrive in Washington from Arlington National Cemetery during their "Freedom Ride" Sunday, May 25, 2003. The rainy weather did not discourage the thousands of bikers from across the nation, who paid tribute to prisoners of war and missing in action during the16th Annual Rolling Thunder Memorial Day celebrations.

2003
Associated Press

Bikers pass the Lincoln Memorial as they arrive in Washington from Arlington National Cemetery during their "Freedom Ride" Sunday, May 25, 2003. The rainy weather did not discourage the thousands of bikers from across the nation, who paid tribute to prisoners of war and missing in action during the16th Annual Rolling Thunder Memorial Day celebrations.

2011
Associated Press

In a May 23, 2011 photo, a marker in Hampton Park in Charleston, S.C., commemorates the 1865 honoring of Union soldiers who died at a Confederate prisoner of war camp on the site. Some historians contend that the event in the city where the Civil War began marks the first Memorial Day observance in the United States.

2013
Associated Press

A rose is placed at the wall of the the Vietnam Veterans Memorial, ahead of Memorial Day in Washington, Sunday, May 26, 2013.

2013
Associated Press

A member of the U.S. Army's 3rd Infantry Regiment "The Old Guard," stands at attention during the arrival of President Barack Obama's arrival at Arlington National Cemetery Monday, May 27, 2013, in Arlington, Va.

2014
Associated Press

Associated Veterans of Bakersfield Honor Guard played taps and music representing each branch of the military Sunday, May 25, 2014 in Bakersfield, Calif. during the Remembering Our Kern County Fallen Heroes Memorial Day recognition.

2014
Associated Press

Marine Cpl. Brayden Hardy, 14, of Boise, straightens American flags at the Idaho State Veteran's Cemetery in Boise, Idaho, Saturday, May 24, 2014, for Memorial Day. Thousands of flags were placed around the cemetery.

2014
Associated Press

Marine Cpl. Zach Powers salutes participates of Rolling Thunder 'Ride for Freedom' event in Washington, Sunday, May 25, 2014.

2014
Associated Press

Visitors console each other at the Vietnam Veterans Memorial in Washington, Saturday, May 24, 2014, ahead of Memorial Day Monday.