John S.D. Eisenhower, the son of President Dwight D. Eisenhower who forged a reputation in his own right as a military historian, died Saturday at his home in Trappe, Md., on the Eastern Shore. He was 91.
The death of Mr. Eisenhower, who had been the oldest surviving child of a U.S. president, was announced by his family.
John Eisenhower was an Army officer in World War II and the Korean War and a national security adviser during his father's presidency, but at that point he was still viewed primarily as the son of Ike, the American hero.
When he graduated from the U.S. Military Academy at West Point on June 6, 1944, photographers gathered for an image of John Eisenhower, the Army's new second lieutenant, with his mother. But he was seen as a footnote to a historic day: Gen. Dwight D. Eisenhower, the supreme Allied commander, had just announced the D-Day landings on the beaches of Normandy.
John Eisenhower's public image began to change in 1969 with the publication of his first book, "The Bitter Woods," a history of the Battle of the Bulge in World War II. It was a best-seller, and he later wrote about the Mexican-American War and World War I.
Dwight D. Eisenhower died in March 1969. Two months later, John Eisenhower took up his duties as ambassador to Belgium. He was appointed by President Richard M. Nixon, vice president under Eisenhower and the father-in-law of John Eisenhower's son, David, who married Julie Nixon.
After two years as an ambassador, John Eisenhower published his memoir, "Strictly Personal."
"So Far From God: The U.S. War With Mexico, 1846-1848" was his first book with no connection to his father's career.
When it was published in 1989, John Eisenhower, a reserved figure who bore a strong resemblance to his father, reflected on how his life had invariably been defined. "I was patted on the head as the great man's son," he told USA Today.
"I said: 'The hell with it. I'm going to do something my old man couldn't get into.'"
The book was well received, prompting him to remark, "God, it feels great."
John Sheldon Doud Eisenhower was born in Denver while his father was stationed at an Army post in Panama. As a child, he toured World War I battle sites with his father, who was writing an Army guidebook to them. He attended high school in the Philippines during his father's tour there and followed his path by entering West Point in July 1941.When Lt. Eisenhower graduated, Gen. George C. Marshall, the Army chief of staff, directed him to spend his brief leave with his father to help him cope with the tensions arising from the Normandy invasion. The son was soon thrilled to be aboard a Flying Fortress bomber, heading over the English Channel to visit the battlefront.
But, as he recalled in his memoir, "I was not only his son; I was a young lieutenant who needed on occasion to be straightened out."
At one point, he wrote, "I asked him in all earnestness: 'If we should meet an officer who ranks above me but below you, how do we handle this? Should I salute first and when they return my salute, do you return theirs?'
"Dad's annoyed reaction was short. 'John, there isn't an officer in this theater who doesn't rank above you and below me.' "
John Eisenhower hoped to see combat as an infantry platoon commander, but his father's fellow commanders, Gen. Omar N. Bradley and Lt. Gen. George S. Patton Jr., feared the impact on his father if he were killed in action or captured. He was assigned to intelligence and administrative duties in England and Germany.
He later earned a master's degree in English and comparative literature from Columbia University, taught English at West Point and finally experienced combat at the beginning of a yearlong tour in the Korean War.
Just after his father won the Republican presidential nomination in 1952, John Eisenhower discussed his coming deployment to Korea with him. Writing in The New York Times in 2008, he recalled that his father had accepted his decision to seek combat but "had a firm condition: Under no circumstances must I ever be captured." That, he said, was because his father could have been forced to resign the presidency if the enemy had threatened him with blackmail.
"I agreed to that condition wholeheartedly," Mr. Eisenhower wrote. "I would take my life before being captured."
Later, he came to believe that the son of a president or vice president should not be allowed to serve in combat, in order to free the parent of "worries about an individual soldier, especially a child."
Mr. Eisenhower was a White House adviser on national security affairs during his father's second term and later worked with him on his presidential memoirs, "Mandate for Change" and "Waging Peace." He retired from the regular Army as a lieutenant colonel in 1963 and became a brigadier general in the Reserves.
President Barack Obama said in a statement on Sunday that Mr. Eisenhower had lived "a big and quintessentially American life -- one of patriotism and character, learning and teaching, and a deep and abiding sense of service to his country."
After serving as ambassador to Belgium from 1969 to 1971, Mr. Eisenhower resumed a writing career with his memoir.
Stephen E. Ambrose wrote in his biography "Eisenhower" that when John was a child, his father gave him "sharp verbal dressing downs for transgressions, which, given Eisenhower's standards, were frequent." But Mr. Ambrose added that "overall they got along fine," and later "Eisenhower included his son in as many of his activities as possible.
In his final years, John Eisenhower joined family members in opposing the design for a proposed memorial to his father near the National Mall, saying it was too extravagant. The project's fate is uncertain.