They are remembered as the heroes and trailblazers of their time: Brothers who grew up to enlist together in the Army, women who became the first female Marines and immigrants who fought for the American values they came to embrace.

One hundred years after the United States entered World War I, relatives of those who served in one of the most influential conflicts in world history are sharing their stories online to mark how America’s entry into the war on April 6, 1917, changed lives forever.

“We feel really strongly that this centennial is a unique moment to bring back to life the experiences of those who served in Europe during World War I,” Monique Seefried, commissioner of the U.S. World War One Centennial Commission, told Fox News. The commission’s website features the “genealogy project,” where the stories are posted.

More than 4.7 million Americans served in World War I and 53,402 died in combat. Their sacrifices are being honored Thursday in an ongoing ceremony at the National World War I Museum and Memorial in Kansas City, which is being livestreamed online.

“America entered the war to bring liberty, democracy and peace to the world after almost three years of unprecedented hardship, strife and horror,” Robert Dalessandro, chairman of the Centennial Commission, told an audience Thursday. “The brave men and women who served in World War I would become the parents of The Greatest Generation that would lead the world to liberty and peace for over 30 years.”

The ceremony consists of the reading of passages from American writings a century ago about the U.S. decision to jump into the war. It will also include performances from a military band and flyovers from U.S. aircraft and the Patrouille de France – the French Air Force’s acrobatics team – which is in the midst of its first tour of the U.S. in more than 30 years.

“The purpose is to tell the story of how did we get there -- what was happening in the U.S., and what were the voices that brought us there,” Matthew Naylor, Museum president and CEO, told Fox News.

In one of the passages read Thursday, Mary Gladwin, an Ohioan and one of the first American Red Cross nurses to go to Europe during the war, wrote how the sounds of gunfire were constant at her hospital in Serbia.

“There was no time during 24 hours in the first six months that some of the guns were not fired,” a speaker read. “My room was a little whitewashed one. Every time one of the big French guns would fire it would illuminate all the wall, then I would hear the boom of the guns.”

Among the invitees who will attend the ceremony: Acting Secretary of the U.S. Army Robert M. Speer, ambassadors from France, Hungary, Italy and other European countries and descendants of notable World War I leaders and soldiers, such as the granddaughters of General George S. Patton and President Dwight D. Eisenhower. Students will be able to watch in their classrooms through participating TV stations.

In addition to a flyover at the April 6 ceremony, the Patrouille De France (PAF) will be flying alongside the Navy’s Blue Angels and Air Force’s Thunderbirds at upcoming airshows in Florida and Nevada, as part of an ongoing tour across the U.S.

Pilots from both U.S. teams will fly in the backseats of PAF aircraft, which will be adorned with portraits of French World War I flying aces.

“There are not so many countries that have never fought against each other. And the U.S. and France have always been allied,” Lt. Col. Gauthier Dewas of the PAF told Fox News. “We want to celebrate those people from America who came to France to help us when we were in trouble.”

Dewas said attendees of the shows should expect something “very different” than performances by the Thunderbirds and Blue Angels, as the PAF flies eight aircraft, which are smaller. Among the maneuvers will be the painting of the French and American flags using colored smoke.

“The Patrouille de France’s U.S. Tour celebrates this exceptional relationship, a relationship of steadfast allies determined to share their excellence in aeronautics to defend our shared values,” the group said in a statement.

Back at the museum, two new exhibits have opened up to coincide with the centennial events.

In “Vive L’amerique!: French Children Welcome Their American Ally,” drawings and essays from French school children after Americans landed in France in 1917 will be showcased.

One drawing shows the U.S. and France trying to hold hands across the Atlantic Ocean, while another displays an American soldier holding up Old Glory.

“We came to know from some contact of a school in Paris who asked the children to draw and write essays right through the war about the experience of living in war,” Naylor told Fox News, adding that the works were kept in archives at a museum in Paris and were never before publicly exhibited.

Another exhibition features modern-day images of the battlefields and locations of the Western Front where Americans fought. Outside the Museum, 30 enlarged panels have been installed – some as large as 42-square-feet – to display the photos.

“Our objective is to remember those who served and the lives who were lost, examine the catastrophe and how it restructured the world and its enduring impact,” Naylor said.