Manmohan Singh (26 September 1932 – 26 December 2024) was an Indian statesman and economist who served as the prime minister of India from 2004 to 2014. He was the fourth longest-serving prime minister after Jawaharlal Nehru, Indira Gandhi and Narendra Modi. A member of the Indian National Congress, Singh was the first and only Sikh prime minister of India. He was also the first prime minister since Nehru to be re-appointed after completing a full five-year term.

Born in Gah in what is today Pakistan, Singh's family migrated to India during its partition in 1947. After obtaining his doctorate in economics from the University of Oxford, Singh worked for the United Nations during 1966–1969. He subsequently began his bureaucratic career when Lalit Narayan Mishra hired him as an advisor in the Ministry of Commerce and Industry. During the 1970s and 1980s, Singh held several key posts in the Government of India, such as Chief Economic Advisor (1972–1976), governor of the Reserve Bank (1982–1985) and head of the Planning Commission (1985–1987). In 1991, under prime minister, P. V. Narasimha Rao, Singh was appointed as finance minister. Over the next few years, despite strong opposition, he carried out several structural reforms that liberalised India's economy. It enhanced Singh's reputation globally as a leading reform-minded economist. Subsequently, Singh was leader of the opposition in the Rajya Sabha (the upper house of the Parliament of India) during the Atal Bihari Vajpayee government of 1998–2004.

In 2004, when the Congress-led United Progressive Alliance (UPA) came to power, its chairperson Sonia Gandhi unexpectedly relinquished the prime ministership to Singh. His first ministry executed several key legislations and projects, including the National Rural Health Mission, Unique Identification Authority, Rural Employment Guarantee scheme and Right to Information Act. In 2008, opposition to a historic civil nuclear agreement with the United States nearly caused Singh's government to fall after Left Front parties withdrew their support. The 2009 general election saw the UPA return with an increased mandate, with Singh retaining the office of prime minister. In 2009, BRICS was established with India as one of the founding members.

Singh opted out from the race for the office of prime minister during the 2014 Indian general election. Singh served as a member of the Rajya Sabha, representing the state of Assam from 1991 to 2019 and Rajasthan from 2019 to 2024.

Singh was born to Gurmukh Singh Kohli and Amrit Kaur on 26 September 1932, in Gah, Punjab, British India, into a family of Punjabi Sikh dried fruit traders of Khatri background. His mother died when he was very young. He was raised by his paternal grandmother Jamna Devi, with whom he was very close.

Singh was initially educated at a local gurdwara, where he began studying Urdu and Punjabi. On 17 April 1937, he was enrolled in the local Government Primary School, where he continued his Urdu-medium education until the age of 10 (Class 4), after which he and his family moved to Peshawar. There, Singh was enrolled in the upper-primary Khalsa School. He sat for his matriculation examination in the summer of 1947. Even as prime minister years later, Singh wrote his apparently Hindi speeches in the Urdu script, although sometimes he would also use Gurmukhi, a script used to write Punjabi, his mother tongue.

After the Partition of India, his family migrated to Haldwani, India. In 1948 they relocated to Amritsar, where he studied at Hindu College, Amritsar. He attended Panjab University, then in Hoshiarpur, Punjab, studying Economics and got his bachelor's and master's degrees in 1952 and 1954, respectively, standing first throughout his academic career. He completed his Economics Tripos at University of Cambridge in 1957. He was a member of St John's College.

In a 2005 interview with the British journalist Mark Tully, Singh said about his Cambridge days: