[caption id="attachment_19213" align="aligncenter" width="369" caption="Helmet worn by Peter L. Robinson in World War I"][/caption] The Civil War, which left virtually no community in the country untouched, also changed the way Americans grieved for those who died in battle. At the end of the war, mourners in both northern and southern states began decorating the graves of fallen soldiers with flags and flowers. Seeking to unite the local practices into a national observance, General John A. Logan, leader of the Union Army's veterans' association, officially proclaimed Decoration Day on May 5, 1868. The holiday was first observed on May 30 of that same year, with a large ceremony at Arlington National Cemetery, across the river from Washington, D.C. Honoring the soldiers who died fighting in the Civil War, the holiday was recognized by all of the northern states by 1890. But many southern states, however, refused to acknowledge the holiday. Despite this, Decoration Day continued to grow, and by the end of the 19th century it had been renamed Memorial Day. It wasn't until after World War I, when the holiday was expanded to honor all Americans who died in battle, and at last recognized by most states. Memorial Day became an official federal holiday in 1971 and is now celebrated on the fourth Monday in May. Currently on display at the National Museum of American History is the exhibition "The Price of Freedom: American at War," which displays a number of artifacts from American armed conflicts. With the help of Jennifer Jones, chair and curator of the Armed Forces History Division at the musem , we've selected a few that are not to be missed. Tricorn Hat— During the Revolutionary War (1775-1783), militia troops did not have uniforms, instead, they wore their civilian clothes into battle. This black felt tricorn hat was worn by Colonel Jonathan Pettibone, a member of the 18th Regiment, Connecticut Militia. When Col. Pettibone was killed in battle, the hat was worn by his son, Jonathan Pettibone, Jr. Battlefield Relics— General Winfield S. Hancock, an 1844 graduate of West Point and a veteran of the Mexican-American War, was considered one of the best commanders in the Union army. When John F. Reynolds died in an early battle at Gettysburg, Hancock was selected to take over that wing of the army. His leadership and tactical skill in battle made him a formidable opponent. These battlefield relics in a wooden frame were presented to him at Gettysburg in 1885. Hancock would later be chosen as the Democratic nominee for President of the United States in 1880, when he was narrowly defeated by James Garfield. Christian Fleetwood's Medal of Honor— Sergeant Major Christian Fleetwood was a free man of color born in Baltimore, Md. Educated at the Ashmun Institute (later Lincoln University) in Oxford, PA, Fleetwood also traveled to Liberia as a young man. When the Civil War disrupted trade with the country, he enlisted into the 4th Regiment U.S. Colored Infantry of the Union Army. In 1864, during the battle at Chaffin's Farm, the 22-year-old Fleetwood carried the American flag through battle after two other color bearers had been shot down. For this act of bravery, he was awarded the Medal of Honor. Cher Ami— During World War I (1917-1918), 600 birds were owned and flown by the U.S. Army Signal Corps in France. One of those birds was Cher Ami, a Black Check cock carrier pigeon, who delivered 12 important messages during his service. Cher Ami was shot and injured during his last mission, but still managed to return carrying an important message about isolated troops needing relief and help. Cher Ami was awarded the French "Croix de Guerre" for his heroic service and returned to the U.S. where he died in Fort Monmouth, NJ in 1919 as a result of his wounds. Gold Star Pin— The Women's Committee of National Defenses recommended to President Woodrow Wilson that American women wear a black arm band adorned with a gold star in lieu of traditional mourning attire. In May 1918, Wilson agreed and coined the term "Gold Star Mother," in a letter to the committee. The American Gold Star Mothers, Inc. is a nonpolitical, nondenominational nonprofit organization open to all mothers of fallen soldiers "as well as those who have a service-related death." The "Gold Star" pin honors their loss, however; the actual Gold Star Pins are awarded by the Department of Defense to relatives of the deceased, not just mothers. Remember Pearl Harbor Lapel Pin— After the military base of Pearl Harbor was bombed on December 7, 1941, Americans mobilized in support of World War II (1941-1945) with the patriotic cry, "Remember Pearl Harbor." Thousands of buttons and pins were printed and distributed to both remind and rally Americans behind the war effort. POW Bracelets— In 1970, Carol Bates Brown and Kay Hunter were two college students looking for a way to support U.S. troops fighting in the Vietnam War (1956-1975), when they came up with the idea for POW bracelets. Worn to honor and increase awareness about Prisoners of War and soldiers who are Missing in Action, the bracelets were traditionally worn until the POW returned to the U.S., whereupon the bracelet was presented to the former prisoner. Since 1970, millions of bracelets have been distributed nationwide. At the National Museum of African American History and Culture, curators there shared with us a few patriotic artifacts they have already acquired— a sneak peak at what visitors can expect when the museum opens on the Mall in 2015. Early American Powder Horn— Prince Simbo, a former slave and resident of Glastonbury, Connecticut, used this horn during the Revolutionary War (1775-1783), during which he served as a private in the Seventh Regiment, Connecticut. Binoculars & Helmet used by Peter L. Robinson, Sr.—First Lieutenant Peter L. Robinson served in the U.S. Army during World War I (1917-1918). After his service, he graduated from law school and went on to teach military science at Armstrong High School in Washington, D.C. Tuskegee Airmen Congressional Gold Medal— This medal was awarded to the famous aviators by President Bush on March 29, 2007. At the ceremony, the president said, ""These men in our presence felt a special sense of urgency. They were fighting two wars. One was in Europe and the other took place in the hearts and minds of our citizens."