OAKLAND (KPIX) – On this Memorial Day, there was a guided walking tour tracing Oakland’s ties to the Civil War, the conflict that inspired the origins of the holiday.

“Memorial Day, as we know it, would not exist without this May 5th, 1868 declaration by the Grand Army of the Republic,” explains historian Dennis Evanosky as he guided the group to a corner of Mountain View Cemetery.

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Buried here is a collection of men who survived those four years when Americans killed each other in staggering numbers.

“They very simply came here after the war, lived their lives out here,” says Evanosky.

Some of them, like writer Jack London’s stepfather, became notable.

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Rossell Galbraith O’Brien was born in Dublin, Ireland and came to the United States at the age of 10. He was a 2nd Lieutenant with the Illinois Volunteers by the age of 17, but he left his real legacy, when he moved west after the war.

“In his small organization,” Evanosky explains, “he urged all members of his command to stand and remove their hats whenever the national anthem is played.”

It was those survivors who decided that the nation’s dead should be honored on Decoration Day, a day for the survivors to decorate graves with flowers.

The dates on the tombstones tell the rest of the story. When those veterans started disappearing, efforts were made to honor them, thus a Civil War plot like this one, which was started in 1880.

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It has been restored in recent years, and guided tours are offered once a month.