ATLANTA (DPA) - They were modest brick buildings, without soaring Gothic spires, elaborate rosette windows or roofs carved of 12th century timber.

But the three houses of worship that burned down over the last month in a rural part of south Louisiana were long-time pillars of their African American congregations. To those who prayed there, they were no less sacred than the historic Notre-Dame Cathedral in Paris.

Not that many other people saw it that way. On Sunday (April 14), a crowdfunding site for the three humble churches had pledges totalling just under US$50,000 (S$67,780).

Then on Monday, after flames consumed the roof and spire of the 800-year-old Gothic French landmark and people across the world vowed to rebuild it, calls rang out for solidarity with Louisiana.

"The rebuild of Notre-Dame will be well-funded," journalist Yashar Ali said on Twitter as he promoted the fundraiser. "In the past month, three historically black churches in Louisiana were destroyed by a racist arsonist. He has been charged with hate crimes, but these churches need your help."

By Wednesday morning, the total raised was US$1.5 million.

While the Notre-Dame fire is thought to be accidental, Louisiana officials say the three black Louisiana churches were deliberately set ablaze.

St Landry Parish officials have arrested and charged Holden Matthews, the 21-year-old son of a deputy sheriff, with setting the fires that devastated three churches - St Mary Baptist Church, Greater Union Baptist Church and Mount Pleasant Baptist Church - in St Landry Parish over 10 days in March and April.

Earlier this week, local prosecutors also charged Holden, who is white, with hate crimes for allegedly having a racial motive.

The sense of loss is still sinking in for the congregants.

Mr David Sylvester, a 56-year-old deacon of St Mary Baptist Church on the rural outskirts of Port Barre, got married there and watched two of his children get baptized inside. His brother serves as pastor, and their mother and family are buried in the small cemetery out back.

He said the church, founded 147 years ago, has been rebuilt several times, including once after a fire.

"The church is the people," he said. "We're going to stick together regardless of whether the building is there."

For Ms Norma Mason, a 51-year-old retired schoolteacher, Mount Pleasant Baptist Church in Opelousas was also more than just a building.

At 25, Ms Mason got married inside the squat red brick building with a simple white steeple and bell tower. She baptized her two children there, memorialised her husband and watched her grandson become an altar boy.

Her fondest memory: preparing ham sandwiches, chili dogs and pies for the children who attended Bible school.

"I would be ready to go Sundays," she said. "Even if I was sick, I'd make sure to go."

Ms Mason said she is hopeful that the church will be rebuilt.

"I am very thankful for all the donations," she said. "I know there is a God."

The burning of the Louisiana churches recalled some of the nation's most painful history.

Violence against black churches surged in the decades after the end of slavery and became a way of intimidating and punishing the black community, said Mr Mark Potok, a senior fellow at the Centre for Analysis of the Radical Right, an international network of scholars.

"Historically, when slavery was still enforced, the black church was not separate," he said.

"It's only after the slaves are freed we saw the development of (the) real black church that's independent."

The civil rights movement saw another rise in violence against black churches, which were not only houses of worship, but also spaces where people organised politically and socially and educated younger people without fear.

In Birmingham, Alabama, in 1963, the Ku Klux Klan bombed the 16th Street Baptist Church - a meeting place for civil rights leaders - killing four children.

Black churches are often where young adults got their first public speaking experience or got musical training, said associate professor Valerie Cooper, , who teaches Religion and Society and Black Church Studies at Duke Divinity School.

And because black churches were so central to the community, attacking them became a way to terrorise the community, she said.

"Black churches are places where blackness is honoured," associate professor Cooper said.

"They celebrate blackness in a society that often does not."

Increases in attacks against religious and racial minorities drove a 17 per cent rise in hate crimes in 2017, according to the FBI's most recent accounting.

The fundraising campaign for the black churches was launched last week by the Seventh District Baptist Association, a 149-year-old nonprofit group that includes 54 Baptist churches in south-west Louisiana.

Any donations, it said, would be split evenly among the three churches that burned to rebuild their sanctuaries and replace pews, sound systems and musical instruments that were destroyed.

"I am donating because historic black churches are no less historic or important than Notre-Dame!" one donor, Mr Stuart Feen, wrote on the fundraising website.

"We honour all places of worship," wrote Mr John Holding. "Blessings in your efforts to rebuild."

"You are someone's Notre-Dame but you suffer more because you were harmed by cruelty," wrote a couple, Jane and Roger. "We admire you and believe you will return strong."

Many American leaders were quick to comment as Notre-Dame burned.

"It is heartbreaking to see a house of God in flames," Vice-President Mike Pence said on Twitter shortly after flames engulfed Notre-Dame's spire.

On Tuesday, the White House offered to help France rebuild an "irreplaceable symbol of Western civilization".

The Trump administration did not speak out about the burning of the Louisiana churches.

Some Americans questioned why the blaze of a historic church across the Atlantic received more sympathy than out-of-the-way rural churches in the US that were deliberately burned.

Associate professor Cooper, the divinity professor, said the conversation has come up in her class, where people have mourned not only for Notre-Dame but also black churches.

"We shouldn't care more for Notre-Dame than the churches in our backyard," she said.