US President Joe Biden on Monday hailed the start of the five-day festival of Diwali – the celebration that symbolizes the victory of light over darkness and is celebrated by Hindus, Jains and Sikhs around the world, especially in India.

Biden kicked off the festivities at the White House by lighting a small prayer lamp known as a diya. Several hundred guests – including South Asian government officials, elected officials, prominent community members and others – wore silk and embroidered finery and crowded into the White House’s vast, chandelier-adorned East Room for the occasion.

But Biden took the opportunity to shed light on someone who wasn’t in the crowd: Vice President Kamala Harris, the most prominent South Asian American, who has been busy on the campaign trail as the election quickly approaches. Her late mother emigrated to the United States from the then Indian city of Madras, now called Chennai.

“One of the things we bonded over was the role each of our mothers played in our lives,” Biden said. “They come from different places, different generations, different lives, but they shared a basic belief about America: only in America anything is possible. Only in America.”

And, he said, after hundreds of years of struggle, South Asian Americans have made the U.S. their home.

“Diwali is celebrated openly and proudly here at the White House,” he said. “And besides, this isn’t my house. This is your house.”

According to the Indian government, the festival begins on the darkest night of the year, according to the Hindu lunar calendar: October 31. The day is a national holiday.

Visibly moved by the event, Surgeon General Vivek Murthy shared how his parents’ faith illuminated their path after they immigrated to the US from India.

“That is the message of Diwali,” he said. “Always choose light, whatever the future brings. Whatever the future holds, it is our light and our fierce commitment to each other that will guide us to a better day.”

And joining the festivities from a distance was Sunita Williams, commander of the International Space Station. Her father immigrated to the US from India; her mother, from Slovenia. She spoke to the White House audience via a recorded message from 420 kilometers (260 miles) above Earth.

“On this day, I think specifically of my father, who immigrated to the U.S. from India,” she said. “He preserved and shared his cultural roots by teaching us about Diwali and other Indian festivals. Diwali is a time of joy because good prevails in the world. I am so grateful to have grown up in a multicultural household where our parents encouraged us to seek opportunities and reach for the stars.”

Monday’s reception marks the latest in a series of presidential Diwali celebrations dating back to President George W. Bush’s term in office. Presidents Barack Obama and Donald Trump also held Diwali celebrations.

The festival marks the return of the mythical Lord Ram, mentioned in Sanskrit scripture as a reincarnation of the god Vishnu, from exile after 14 years. The people of his kingdom, Ayodhya, lit lamps to light his path home – a tradition that merriment continues today with lamps and fireworks. Indian Americans make up the largest non-mixed Asian group in the United States, with nearly 4.4 million people identifying as 100% Indian ancestry, according to the US Census Bureau.

Today, revelers around the world honor the occasion with new attire, extravagant decorations and copious amounts of sugar-laden treats.

This year saw Indian Prime Minister Narendra Modi, the biggest proponent of a Hindu nationalist movement known as Hindutva, have a sweet named after him. The so-called “Modi Laddu” – the Modi Ball – is made from saffron, clarified butter, pistachios, almonds and rose water.

But there is also a hint of bitterness in the way India celebrates this holiday.

Modi was the driving force behind the reconstruction of a Hindu temple in Ayodhya, at what was believed to be Ram’s birthplace. In 1992, a Hindu mob demolished a mosque there, sparking deadly religious riots that were the worst since India’s independence, killing more than 2,000 people. Modi spent years raising money to build a huge Hindu temple on the ruins. He opened it earlier this year and said, “Today our Ram has come.”