Mr Modi’s landslide, the most resounding election victory India has seen in 30 years, was welcomed with a rally on India’s stock markets.
The election was the world’s largest yet. Staggered over five weeks, a record of more than 500 million ballots were cast from the Himalayas in the north to the tropical south for a record 66 per cent turnout.
There were raucous celebrations at offices across the country of Mr Modi’s Bharatiya Janata Party (BJP).
The BJP looked certain of a parliamentary majority, giving the 63-year-old former tea-seller ample room to advance economic reforms which were started 23 years ago by current prime minister Manmohan Singh but stalled in recent years.
Mr Singh’s Congress Party suffered its worst wipeout yet, a big boost to Mr Modi’s goal of ending the dominance of the Nehru-Gandhi family that has governed for most of the 67 years of independent India. Mr Singh, whose party looked set to win less than 50 of the 543 parliamentary seats at stake, congratulated Mr Modi in a telephone call.
Crowds surged around Mr Modi’s car after he visited his mother’s home in the western state of Gujarat, where he has been chief minister since 2001.
He sent a message saying “India has won” that set a record as the country’s most retweeted Twitter post.
The desire for change has been so strong that voters put aside concerns about Mr Modi’s Hindu-centric politics.
“I’m so happy because all of India wanted a strong government,” shouted software engineer Vinod Rai at the BJP’s Delhi headquarters.
With more than six times the seats of its closest rival, Mr Modi’s is the most decisive mandate for a leader since the 1984 assassination of prime minister Indira Gandhi propelled her son to office. Since 1989, India has been governed by coalitions.
The BJP had won or was winning in 283 seats in parliament, counting trends showed, comfortably across the halfway mark of 272 required to rule.
Responding to the news, Indian markets got off to a roaring start, with the rupee breaking below 59 to the US dollar, an 11-month high, and the benchmark stock index jumping 6 per cent to a record high before paring its gains.
Unlike his predecessors, Mr Modi will not have to deal with unruly partners as he implements reform.
That could usher in profound economic changes, and he will try to replicate his success in attracting investment and building infrastructure in Gujarat, the state he has governed for more than 12 years.
However, with India’s economy suffering its worst slowdown since the 1980s and battling high inflation, it will not be an easy task to meet the hopes of millions who have bought into the idea that Mr Modi will quickly push their country on to the top table of economic powers.
His party also lacks strength in the upper house of parliament, where backing is needed for legislation to pass.
Since being named as his party’s candidate last September, Mr Modi has flown 186,000 miles and addressed 457 rallies.
He contrasted his humble roots with the cloistered life of privilege of his dynastic rivals.
He ran circles around his opponent Rahul Gandhi, 43, from the Congress Party, which his family has dominated since his great-grandfather, Jawaharlal Nehru, led India to independence from Britain in 1947.