Washington (CNN) -- Alexander Haig, who managed the Nixon administration during the Watergate crisis and served a controversial stint as secretary of state under President Reagan, died on Saturday. He was 85.

Haig died at Johns Hopkins Hospital in Baltimore, Maryland, after he was admitted there on January 28, spokesman Gary Stephenson said.

"He served his country well. For that he should be remembered," said William Bennett, who was secretary of education during the Reagan administration. "He carried himself well. He carried himself with dignity and honor."

The White House issued a statement mourning Haig, saying he "exemplified our finest warrior-diplomat tradition of those who dedicate their lives to public service."

A top official in the administrations of three presidents -- Richard Nixon, Gerald Ford and Ronald Reagan -- Haig served as Nixon's chief of staff during the Watergate political crisis, a scandal that dogged the administration in the 1970s.

"There was a time during the Watergate crisis when President Nixon was nearly incapacitated," said political analyst and CNN contributor David Gergen, who worked with Haig during the Nixon and Reagan administrations. "He had a hard time focusing, so obviously obsessed with the scandal and the gathering storms around him. I watched Al Haig keep the government moving. I thought it was a great act of statesmanship and service to the country."

Haig became secretary of state during the Reagan administration and drew controversy for his much-criticized remark on television after the president was shot and wounded by John Hinckley in March 1981.

"As of now, I am in control here in the White House," Haig said as Vice President George H.W. Bush was headed to Washington from Texas.

Haig said he wasn't bypassing the rules; he was just trying to manage the crisis until the vice president arrived. However, he was highly criticized for his behavior, and many observers believe it doomed his political ambitions.

Born December 2, 1924, in Bala Cynwyd, Pennsylvania, a suburb of Philadelphia, Alexander Meigs Haig Jr. was raised by his mother after he lost his father at age 10. He attended the University of Notre Dame for two years before transferring to the U.S. Military Academy in 1944.

After his graduation in 1947, he served in Japan and later served on Gen. Douglas MacArthur's staff in Japan during the Korean War.

He also served in Vietnam, where he earned the distinguished service cross for heroism in combat. He also won the Purple Heart and Silver Star twice.

Haig served as supreme allied commander of NATO forces in Europe for five years. There was an assassination attempt on him in Brussels in 1979 as he was being driven to NATO headquarters.

A public official known for his loyalty, Haig had hawkish foreign policy views, and Gergen said he could be tough and "combustible."

"He was first and foremost a soldier," Gergen said.

Haig was assistant to National Security Adviser Henry Kissinger in the Nixon White House and was involved in the Paris peace agreements that brought an end to the U.S. involvement in the Vietnam War.

He was long rumored to be Deep Throat, the Washington Post's inside source on the Watergate break-in and cover-up that eventually destroyed Nixon's presidency. W. Mark Felt, then a high-ranking FBI official, declared in 2005 that he was the source.

"Great tensions" in the Reagan administration simmered over his stances, and Gergen said, "There was a sense in the White House that he was grabbing too much power.

"He wanted to be the, quote, vicar of foreign policy, and there was a lot of pushback from the White House on that. He felt that he had been guaranteed by Ronald Reagan a role as a strong secretary of state and the reins of power would be in his hands. He resented the White House staff trying to manage him," Gergen said.

"My own sense is that he has been underappreciated," he said.

TIME: Read why Haig left the Reagan White House

As secretary of state, Haig tried shuttle diplomacy to head off war between Britain and Argentina over the Falkland Islands in 1982, but he failed. He opposed Reagan's handling of Iran and disagreed with the president's plan on aid to the contra rebels in Nicaragua.

He eventually left the Reagan administration after 18 months and made a run for president in 1988, pulling out before the New Hampshire primary. He backed Bob Dole instead of George H.W. Bush when he dropped out.

Former U.S. Ambassador to the U.N. John Bolton announced Haig's death to the Conservative Political Action Conference in Washington on Saturday and called him a patriot.