On Saturday, May 21, the nation is scheduled to celebrate Armed Forces Day, an occasion that is often overshadowed by the better-understood Memorial Day events that come little more than a week later.

On Armed Forces Day, military bases around the United States will show their people, equipment and methods to the American public they support. In an era of demanding military commitments around the world, fewer bases will hold open-house events than in years past, but Americans will flock to the shows that are held.

Best-known and most attended of these events is the Joint Forces Open House and Air Show to be held at Joint Base Andrews, just outside Washington, D.C. The Andrews event will open Friday, May 20, for Department of Defense personnel and their families as well as school-sponsored children. The event will be open to the general public May 21-22 from 8:00 a.m. to 5:00 p.m. The base is expecting 100,000 visitors on Saturday alone – a huge number, but smaller than in previous years because of security precautions.

Long before airfields had fences, gates, or guards, those who fly to defend the nation enjoyed displaying their skills and equipment to the citizens they protect.

In the earliest days of aviation, many airfields were little more than pastures with unpaved runways. Military air pioneers took to the sky in flimsy, fabric-covered biplanes while anyone living nearby was encouraged to observe. In 1910, citizens brought picnic lunches to watch Orville Wright demonstrate an aircraft at Fort Myer, Va.

One of several predecessors of Armed Forces Day was Army Day, first celebrated on May 1, 1928. That day, Army installations held demonstrations for the public, including air shows.       Beginning in 1929, Army Day was changed to April 6, a date coinciding with the U.S. entry into the Great War, later called World War I.  Army Day became a nationwide observance to draw public attention to national defense and bring Americans to open house events.

Navy Day had a spot of its own on the calendar, on Oct. 27 of each year. Between the world wars, veterans’ groups urged each service branch to create a day to honor the founding of their particular service. The Navy League urged Navy leaders to celebrate their service’s achievements – and display them to the taxpayer – on Oct. 27. There was some confusion as to how to choose a date, and it was eventually decided to pick the birthday of President Theodore Roosevelt, who had been an assistant secretary of the Navy and supported a strong Navy as well as the idea of Navy Day. A second reason for picking Oct.r 27 was a 1775 report on that date issued by a special committee of the Continental Congress favoring the purchase of merchant ships as the foundation of an American Navy.

Army Day, Navy Day and similar Coast Guard and Marine Corps events were postponed during World War II, but were replaced by public displays held to sell war bonds. One of the largest military shows ever held in the U.S. took place on the Washington Monument grounds over a two-week period in July 1943. The event exposed the public to thousands of soldiers and hundreds of tanks, planes, and guns, all transported to the center of the nation’s capital. A P-51B Mustang fighter was displayed in the grass across the street from the Department of Commerce. A B-24 Liberator appeared on the Monument grounds. There were impressive flyovers by warplanes.

“Unification” – called “jointness” today – was a buzzword in the postwar era. As military leaders had promised during the war, a Department of Defense was created in 1947, and the Air Force became an independent service branch on Sept. 18 of that year. In 1948 and 1949, public events were held on Air Force Day, on Aug. 1 – for those two years only.

On Aug. 31, 1949, Secretary of Defense Louis Johnson announced the creation of an Armed Forces Day to replace Army, Navy, and Air Force days. There was irony in the timing of Johnson’s call for “unification.” At the time, Air Force generals seeking the B-36 bomber were locking horns in a furious inter-service battle with Navy admirals who wanted a new aircraft carrier.

The first “joint” public day was celebrated on May 20, 1950 – weeks before the outbreak of the Korean War – with parades, shows, and open houses around the country. The theme for that day was “Teamed for Defense,” which expressed the unification of military service branches under one government department. The largest show was held at Bolling Air Force Base, D.C., which has no runway today but was a busy airfield then.

The Bolling show enabled the public to see the newest the military, including the Air Force, had to offer. Among equipment shown to the public was a C-54 Skymaster transport used in the Berlin Airlift the previous year and a B-50 Superfortress bomber, part of the nation’s evolving strategic nuclear force. There were also speeches and parades.

In peace and war, Armed Forces Day has been held every year since 1950 on the third Saturday in May.