Barack Obama's trip to India Nov 6-9 will be the sixth by a US president since Dwight D Eisenhower became the first to come visiting more than 50 years ago.
Richard Nixon, Jimmy Carter, Bill Clinton and George W Bush were the other US presidents - in that order - to visit the country.
Eisenhower's visit to India in December 1959 was part of his Asia tour, planned ahead of his meeting with Western leaders in Paris.
In his address to the Indian parliament he spoke of "a great awakening" in which the world has come to recognise "that only under a rule of moral law can all of us realise our deepest and noblest aspirations".
Richard Nixon, who became the 37th president, was the second American president to visit India. He made a one-day trip in July 1969, about six months after he assumed presidency.
Nixon's visit came at a politically turbulent period, when then Indian prime minister Indira Gandhi was fighting with her opponents in the Congress party over who should fill the post of president after Zakir Husain died, Dennis Kux, a former US ambassador, wrote in his book "India and the United States: Estranged Democracies 1941-1991".
"When Nixon arrived in Delhi, the public welcome was none of the overwhelming enthusiasm president Eisenhower received 10 years earlier," Kux wrote. His arrival speech largely dealt on the situation in Vietnam and the role of Asia.
"Neither Gandhi nor Nixon displayed much warmth during their discussions. Official meetings were low key, almost perfunctory," he wrote. Nixon flew to Lahore the following day.
Jimmy Carter was the third US president to visit India nine years later, in January 1978. During his three-day stay in the capital, he was caught by microphones telling his aides that a "cold and blunt message" should be delivered to the Indians over its nuclear ambitions.
It also took him to Daulatpur village in Haryana. Carter's mother Lillian Gordy Carter had been a frequent guest at the village headman's house when she was working in India as a Peace Corps volunteer. Carter and first lady Rosalynn visited the home where Lillian had stayed and even presented the village with its first television set. Later Daulatpur was renamed Carterpuri to commemorate the presidential visit, while the day Jan 3 became a village holiday.
Twenty-two years later, in March 2000, Bill Clinton became the fourth US president to visit India. His daughter Chelsea Clinton accompanied him. His itinerary was packed with visits to Agra, Jaipur, Hyderabad and Mumbai besides Delhi. Clinton's five-day trip was the longest by a US president.
In his address to parliament, where he was virtually mobbed by MPs, Clinton favoured talks between India and Pakistan and urged restraint in its nuclear programme.
"Most of the world is moving toward the elimination of nuclear weapons. That goal is not advanced if - in any country in any region - it moves in the other direction," he noted.
George W Bush was the fifth US president to visit India, in March 2006. Bush and first lady Laura barely spent 60 hours - the shortest by a US president after Nixon's 23-hour stopover.
During the visit, India agreed to a separation of its civilian and military nuclear facilities - a key step leading to the signing of the historic India-US civil nuclear agreement.
Besides his meetings in Delhi, Bush took a short trip to Hyderabad where he visited a university.
Barack Obama, the 44th US president, will be the sixth to visit India, and the second after Nixon to come in his first term in office.