Nationwide protests against racism and police brutality that were sparked by the 2020 murder of George Floyd reignited calls to rename the bases, and Congress mandated that they be changed despite opposition from then-president Donald Trump.

"The names of these installations and facilities should inspire all those who call them home, fully reflect the history and the values of the United States, and commemorate the best of the republic that we are all sworn to protect," Austin wrote in a memo on the decision.

The 2021 defense budget required the establishment of a commission to plan for the removal of Confederate-linked "names, symbols, displays, monuments, or paraphernalia" from defense department property, and gave the secretary three years to carry out its recommendations.

"I am committed to implementing all of the commission's recommendations as soon as possible," Austin said in the memo, adding that this will happen when a 90-day waiting period expires in December and will be completed "no later than January 1, 2024."

The changes "will give proud new names that are rooted in their local communities and that honor American heroes whose valor, courage, and patriotism exemplify the very best of the United States military," he wrote.

Trump opposed the renaming effort, tweeting in 2020 that his administration "will not even consider" changing the names of the bases, which "have become part of a Great American Heritage, and a history of Winning, Victory, and Freedom."

He vetoed the defense bill, but Congress overrode it in a blow to the president, who by then had lost the 2020 election to Joe Biden.

All of the bases being renamed are located in Southern states that seceded from the United States and formed the Confederacy, which lost the 1861-1865 Civil War.

They include Fort Benning in Georgia, home to the US Army Infantry School, and Fort Bragg in North Carolina, home to the US Special Forces Command and the storied 82nd Airborne Division.

Fort Benning is currently named after brigadier general Henry Benning, an ardent secessionist who argued for the "superiority" of the white race.

The commission recommended it be renamed Fort Moore to honor US lieutenant general Hal Moore -- who commanded American troops during their first major battle with North Vietnamese forces -- and his wife Julia.

Fort Bragg, named for major general Braxton Bragg, an inept general who was relieved of command, is recommended to become Fort Liberty.