These photos, taken from the 1890s-1950s, show the oldest surviving veterans of the American Civil War, which resulted in the death of more than 600,000 Americans. 

“For 90 years after the last shot of the American Civil War was fired, the men who had fought for the Union and the Confederacy, respectively, continued to meet, and in doing so wielded considerable political power in the nation that had divided them,” reports Mashable.

The Grand Army of the Republic (G.A.R.), a fraternal organization for Union soldiers, was founded in 1866, a year after the end of the war. At its peak in 1890, it had 490,000 members. The association dissolved in 1956, with the death of 109-year-old veteran Albert Woolson.

The G.A.R. became one of the first organized advocacy groups in American politics and was instrumental in electing several U.S. presidents in the late 1800s, including Ulysses S. Grant and William McKinley. The organization was also responsible for helping to make Memorial Day a national holiday.

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In 1956, the year Woolson died, Life Magazine wrote: “The greatest parade in American history has finally come to an end. The Grand Army of the Republic has marched off to join the shadows and no matter how long the nation exists there will never be anything quite like it again.”

On the Confederate side, the United Confederate Veterans (U.C.V.) was formed in 1889 in New Orleans. Its purpose was to promote “social, literary, historical and benevolent” aims. At the group’s peak in the 1890s, some 30,000 veterans and 50,000 guests were present at the annual reunions. At the final reunion, held in 1950, 98-year-old James Moore of Alabama was the only member present.

In 1959, Walter Williams, who said he was 116 at the time, claimed to be the last remaining Civil War veteran alive. Williams, who was from Mississippi, said he fought as a Confederate soldier; however, census data discovered recently indicates that he may have been only eleven when the war ended. William Lundy, from Alabama, also claimed to be one of the last remaining Confederate soldiers. His age is also disputed, with records showing he was born in 1859 not 1848 as he claimed. Lundy died in 1957.

Many Irish fought on both sides of the war. More than 150,000 Irishmen, many recent immigrants, joined the Union Army. Around 25,000 Irish fought for the Confederate side.

To see more of these amazing images, check out the collection on Mashable. 

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