Updated September 5, 2025 at 5:06 PM EDT
President Trump signed an executive order on Friday to give the Department of Defense a new name: the Department of War.
The change returns the department to a name that it carried for much of its history, until it became the Department of Defense in the wake of World War II.
Speaking from the Oval Office, Trump said the rebranding reflected a new tone for the country and its military.
A White House fact sheet explains that under the executive order, the name "Department of War" will serve as a "secondary title" for the Department of Defense.
According to the fact sheet, the order will also authorize Defense Department officials to substitute the word "war" into their titles. For example, the Secretary of Defense could use the title Secretary of War.
Secretary of Defense Pete Hegseth appeared to acknowledge the change in a post on social media on Thursday, writing simply, "DEPARTMENT OF WAR."
President Trump had previously signaled that a change was in the works. During an appearance in the Oval Office last month, Trump said that War Department "just sounded to me better."
It's not clear whether Trump can officially change the name without congressional action. He suggested after signing the order on Friday that the the administration would ask Congress to codify the change into law, but also said "I'm not sure they have to."
"We're going with it, and we're going with it very strongly. There's a question as to whether or not they [Congress] have to, but we'll put it before Congress," Trump said.
Almost from the country's founding, the military was overseen by the War Department, but the sprawling agency took on its current name following an act of Congress in 1949. At the time, the change marked the culmination of an effort by President Harry Truman to unify the Air Force, Army and Navy under the umbrella of a single department.
As the largest department in the U.S. government, even just changing signs, seals and titles could prove costly. In 2023, an Army official told Congress that an effort to rename only nine Army bases would cost taxpayers $39 million.
Danielle Kurtzleben and Quil Lawrence contributed to this report.
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