Described as a “reluctant king” in his first term as prime minister, the soft-spoken Manmohan Singh, who died on Thursday at the age of 92, was arguably one of India’s most successful leaders.

Singh, the first Sikh to lead his nation, served as prime minister from 2004 to 2014, serving a rare two terms. He was undergoing treatment for age-related medical conditions.

He is credited with steering India towards unprecedented economic growth and lifting hundreds of millions out of abject poverty. He rarely served a second term.

“India mourns the loss of one of its most respected leaders,” Prime Minister Narendra Modi said.

He applauded the economist turned politician.

Born into a poor family in the British-ruled part of India that is now Pakistan, Singh studied by candlelight for a place at Cambridge University before going to Oxford, earning a PhD with a thesis on the role of exports and free trade in the Indian economy .

He became a respected economist, then governor of India’s central bank and a government adviser, but had no apparent plans for a political career when he was suddenly elected finance minister in 1991.

During that tenure until 1996, Singh was the architect of reforms that rescued India’s economy from a severe balance of payments crisis, promoted deregulation and other measures that opened the island nation to the world.

Famously quoting Victor Hugo in his first budget speech, he said, “No power on earth can stop an idea whose time has come,” before adding, “India’s emergence as a major economic power in the world is one such idea .”

Singh’s rise to the prime ministership in 2004 was even more unexpected.

She asked him to take over the job of Sonia Gandhi, who led the centre-left Congress party to a surprise victory. Born Italian, she feared her background would be used by Hindu nationalist opponents to attack the government if she led the country.

During a period of unprecedented economic growth, the Singh government shared the spoils of the country’s newfound wealth, introducing welfare programs such as an employment program for the rural poor.

In 2008, his government also struck a landmark deal that allowed for peaceful nuclear trade with the United States for the first time in three decades, paving the way for a strong relationship between New Delhi and Washington.

But his efforts to further open up the Indian economy have often been frustrated by political infighting within his own party and the demands of coalition partners.

‘History will be kinder to me’

And while he was widely respected by other world leaders, Singh always had to defend himself at home against the perception that Sonia Gandhi was the real power in the government.

The widow of former prime minister Rajiv Gandhi, whose family has dominated Indian politics since independence from Britain in 1947, remained the leader of the Congress party and often made key decisions.

Known for his simple lifestyle and reputation for honesty, Singh personally did not consider himself corrupt. But he was attacked for failing to crack down on members of his government as a series of scandals erupted in his second term, sparking mass protests.

In the final years of his prime ministership, India’s growth story, which he helped engineer, was shaken as global economic turbulence and slow government decision-making dented investment sentiment.

In 2012, his government became a minority after the Congress Party’s biggest ally left their coalition in protest against the entry of foreign supermarkets.

Two years later, the Congress was decisively swept by the Bharatiya Janata Party under Narendra Modi, a strongman who promised to end economic stagnation, clean up graft and bring inclusive growth to the hinterland.

But at a press conference just months before he left office, Singh insisted he had done the best he could.

“I honestly believe that history will be kinder to me than the contemporary media or, for that matter, the opposition parties in parliament,” he said.

Singh left behind his wife and three daughters.