Memorial Day, observed on the last Monday of May, unofficially, marks the beginning of the summer season, as we know. But historically, of course, there is much more to it.
Originally known as Decoration Day, according to history.com, it originated after the Civil War and became an official federal holiday in 1971, honoring the men and women who died while serving in the military.
The Civil War claimed more lives than any conflict in U.S. history and required the establishment of the country's first national cemeteries. By the late 1860s, Americans in various towns and cities had begun holding springtime tributes to these fallen soldiers, decorating their graves with flowers and reciting prayers.
In 1966, the federal government declared Waterloo, New York, the official birthplace of Memorial Day. Waterloo—which first celebrated the day on May 5, 1866—was chosen because it hosted an annual, community-wide event, during which businesses closed and residents decorated the graves of soldiers with flowers and flags.
Two years later, General John A. Logan, leader of an organization for Northern Civil War veterans, called for a nationwide day of remembrance. "The 30th of May, 1868, is designated for the purpose of strewing with flowers, or otherwise decorating the graves of comrades who died in defense of their country during the late rebellion, and whose bodies now lie in almost every city, village and hamlet churchyard in the land," he proclaimed.
On the first Decoration Day, 5,000 Americans gathered at Arlington National Cemetery to decorate the graves of the 20,000 Union and Confederate soldiers buried there. By 1890 all of the Nothern States had made Decoration Day an official state holiday. Southern states, however, continued to honor their dead on separate days, It wasn't until after World War I, when the United States found itself embroiled in another major conflict, and the holiday evolved to commemorate American military personnel who died in all wars, and Decoration Day became Memorial Day.
For decades, Memorial Day continued to be observed on May 30. But in 1968 Congress passed the Uniform Monday Holiday Act, which established Memorial Day as the last Monday in May in order to create a three-day weekend for federal employees; the change went into effect in 1971. The same law also declared Memorial Day a federal holiday.