In the US, today is Memorial Day. The purpose of the holiday in today's world is to remember all those who have died but especially veterans of our military. I especially remember my father, Donald King, a 25-year veteran of America's intelligence services who served in WW2 and Korea, and my step-mother, Laura Ann Pratt Hanson King, who served in the Red Cross in the Pacific in WW2.
However, the origin of the holiday was Decoration Day, celebrated by African-Americans in the south after the Civil War. They would go to cemeteries where Union soldiers were buried to repair and decorate the graves. Resentful southern whites either ignored or actively vandalized the graves of the Yankee invaders, so African-Americans, who looked on Union soldiers as liberators, took care of the graves. The long string of Republican administrations in the late 19th century took the holiday up as a national event (Republicans in those days were mostly either black southerners or white WASP northerners - this was the era of Grant, McKinley, Teddy Roosevelt, etc.). White southerners developed their own holiday, Confederate Decoration Day. When I was a kid in Virginia in the 1960s, we got it off, though it was combined with remembrance of Robert E Lee and Thomas Jackson, two Virginian Confederates who had birthdays that were conveniently close together. It was celebrated in January, not a very good time to decorate graves.