Celebrating Memorial Day In The United States

Here's a little bit of history on this observance:

Memorial Day is a day for remembering and honoring military personnel who died in the service of their country, particularly those who died in battle or as a result of wounds sustained in battle.

Three years after the Civil War ended, on May 5, 1868, the head of an organization of Union veterans — the Grand Army of the Republic (GAR) — established Decoration Day as a time for the nation to decorate the graves of the war dead with flowers. Maj. Gen. John A. Logan declared that Decoration Day should be observed on May 30. It is believed that date was chosen because flowers would be in bloom all over the country. The first large observance was held that year at Arlington National Cemetery, across the Potomac River from Washington, D.C.

The gravestones at Arlington National Cemetery are decorated by U.S. flags on Memorial Day weekend.

In 1966, Congress and President Lyndon Johnson declared Waterloo, N.Y., the “birthplace” of Memorial Day. There, a ceremony on May 5, 1866, honored local veterans who had fought in the Civil War. Businesses closed and residents flew flags at half-staff. Supporters of Waterloo’s claim say earlier observances in other places were either informal, not community-wide or one-time events.

By the end of the 19th century, Memorial Day ceremonies were being held on May 30 throughout the nation. State legislatures passed proclamations designating the day, and the Army and Navy adopted regulations for proper observance at their facilities. 

It was not until after World War I, however, that the day was expanded to honor those who have died in all American wars. In 1971, Memorial Day was declared a national holiday by an act of Congress, though it is still often called Decoration Day. It was then also placed on the last Monday in May.

http://usmilitary.about.com/od/theorderlyroom/a/memorialday.htm