The 63-year-old flew into Delhi's main airport in the late morning from his home state of Gujarat to bask in the glory of a landslide for the Bharatiya Janata Party and begin organising his cabinet.
The controversial politician, a former tea boy tainted by anti-Muslim riots on his watch as chief minister in Gujarat, has the strongest mandate of any Indian leader in 30 years.
A crowd of party supporters, waiting at the airport since early morning but entertained by a marching band and thumping dance music, burst through police barricades at the sight of his cavalcade.
He emerged from the door, smiling and flashing victory signs, as many strained for a glimpse and showered the vehicle in rose petals.
"Modi is our lion! He will work for the people of India, he will work for development, he will work for every Indian," shouted Om Dutt, a 39-year-old shop owner, reflecting heady expectations of what he will deliver.
As Modi was driven to party headquarters in the centre of the capital, thousands lined the streets dressed in T-shirts bearing images of his face, with police having to frequently push back well-wishers.
"I thank the BJP workers wholeheartedly," he said at a festive headquarters flanked by senior party figures such as Rajnath Singh and Ravi Shankar Prasad who are likely to take government roles.
The BJP won the first majority in parliament for 30 years on Friday after a campaign by Modi focused on delivering new jobs, development and clean government.
The triumph redrew India's political map, handing him a huge mandate for change, and heaping humiliation on the ruling Gandhi political dynasty whose Congress party has been in power for 10 years. Congress has led India for all but 13 of the 74 years since independence.
In national capitals across the world, leaders readjusted to the change in leadership, with the US and Europe having to quickly embrace a man who has been shunned for a decade.
Modi was boycotted by many Western countries over anti-Muslim riots in 2002 that left about 1,000 dead and a legacy of suspicion that the religious hardliner did too little to prevent the killing.
The strict vegetarian, steeped in the ideology of Hindu nationalism, has always denied wrongdoing and investigators have found no evidence to prosecute him.
The United States, Britain and Australia were quick to extend invitations for him to visit, while Prime Minister Nawaz Sharif from neighbouring Pakistan rang to offer congratulations on an "impressive victory".
Outgoing Prime Minster Manmohan Singh was set to resign on Saturday, ending his 10 years in charge, and a final televised address thanked the Indian people for their support.
"Today India is a far stronger country than it was a decade ago," the 81-year-old said in a typically low-key speech - a contrast to the bombastic high-energy style of his successor.
Modi's supporters on Saturday were insistent that their hero had been elected on a mandate to change India by creating jobs, developing infrastructure and battling endemic corruption.
"He won't discriminate, he will take everyone with him," Shubham Anand, a 19-year-old student, told AFP as he stood waiting for Modi in eastern Delhi. "We need a strong government in India."
In his first comments on Friday night, Modi was at pains to stress that he would work for all of India's 1.2 billion people -- including its 150 million Muslims -- to make this "India's century".
"It is my responsibility to take all of you with me to run this country," Modi said as thousands chanted his name.
Indian newspapers hailed the game-changing election results but said it was vital that Modi allayed the fears of religious minorities who did not vote for him.
"Narendra Modi has scripted one of the most gloriously spectacular political triumphs in the history of independent India," wrote Pratap Bhanu Mehta from the Centre for Policy Research think-tank.
Figures from the Election Commission showed the BJP alone had secured 279 seats and was projected to win another three in the 543-member parliament, the first majority by a single party since 1984.
The Congress, India's national secular force that has ruled for all but 13 years since independence, was left obliterated, holding just 44 seats -- a quarter of its tally in 2009.
The defeat raises questions about the endurance of the Gandhi political dynasty after 43-year-old Rahul, leading campaigning nationally for the first time, suffered such humiliating rejection.