Colin Powell, the first black US secretary of state and top military officer, has died at the age of 84 due to complications from COVID-19.
He was fully vaccinated, his family said in a statement on Facebook.
"We have lost a remarkable and loving husband, father, grandfather and a great American," his family said, offering thanks to the staff of the hospital near Washington DC who treated Powell but providing few details about his illness.
Powell was one of the most prominent black figures in the US for decades.
He served three Republican presidents in senior posts and reached the top of the US military as it was regaining its vigour after the trauma of the Vietnam War.
In a brief statement, the Powell family said he had died on Monday morning from COVID-19, had been fully vaccinated against the disease and it thanked the medical staff at Walter Reed National Medical Center.
It did not address such matters as what vaccine he received or whether he had gotten a booster shot, when he fell ill, when he may have been hospitalised and whether he may have had underlying health conditions that contributed to his illness.
Condolences poured in, including from former president George W Bush.
"Many presidents relied on General Powell's counsel and experience," Bush wrote in a statement.
"He was such a favourite of presidents that he earned the Presidential Medal of Freedom - twice."
Powell served as US national security adviser under president Ronald Reagan from 1987 to 1989.
As a four-star srmy general, he was chairman of the Joint Chiefs of Staff under president George HW Bush during the 1991 Gulf War in which US-led forces expelled Iraqi troops from neighbouring Kuwait.
A moderate Republican and a pragmatist, Powell later served as secretary of state under President George W Bush and was the public face of the erroneous intelligence that the United States cited to justify its March 2003 invasion of Iraq.
He considered running for president in 1996 but his wife Alma's worries about his safety helped him decide otherwise.
In 2008, he broke with his party to endorse Democrat Barack Obama, the first black person elected to the White House.
Illustrating his deep misgivings about the evolution of the Republican Party, Powell endorsed Democrats Hillary Clinton in the 2016 presidential election and Joe Biden last year against Donald Trump.
Powell called Trump a liar who presented a danger to the United States.
Powell will forever be associated with his controversial presentation on February 5, 2003, to the UN Security Council, making president George W Bush's case that Iraqi President Saddam Hussein constituted an imminent danger to the world because of its stockpiles of chemical and biological weapons.
He admitted later that the presentation was rife with inaccuracies and twisted intelligence provided by others in the Bush administration and represented "a blot" that will "always be a part of my record".
Former UK prime minister Tony Blair, who led his country into the Iraq war alongside the US, said on Monday that Powell was a "towering figure" who "still had so much to give".
Australian Associated Press