WASHINGTON - The Headquarters, Department of the Army, will celebrate the U.S. Army birthday on Thursday at 11:30 a.m. in the Pentagon courtyard.The Acting Secretary of the Army, Robert M. Speer, will host a birthday cake cutting ceremony to celebrate 242 years of selfless service to our Nation.The theme for this year's observance is 'Over There! A Celebration of the WWI Soldier,' which commemorates the World War I centennial and the Army's role in supporting that conflict. It was 100 years ago that the United States formed the American Expeditionary Forces and joined its allies to fight in WWI. The ceremony will serve as a time to recognize and remember the contributions of the more than two million Soldiers who served and honor the service and sacrifices of the more than 300,000 killed, wounded or captured while serving overseas.Media interested in attending this event may contact Valerie L. Mongello, Army public affairs, at 703-693-7136 or valerie.l.mongello.civ@mail.mil.For more information about the history of the Army and Army birthday events around the world, visit https://www.army.mil/1775/.