Children play among the wooden shacks beneath the canopy of a massive banyon tree. Lorico Silva stands nearby. He's a member of one of 15 families that live on the Silva Family Quilombo in Porto Alegre. His grandparents moved here 70 years ago.

"This was all forest. Not anymore," says Silva, "They're still trying to kick us out of here, though. Been trying forever. But there's no way we're leaving. This is our home."

This was the first urban quilombo, or community of descendants of African slaves, in Brazil to be officially awarded the title to its land in 2009. But that recognition didn't stop the push by real estate developers to remove the residents.

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Lorico uses a cane and his voice is slurred from a stroke he suffered at a local university as he was recounting the story of a brutal police raid in 2010. The police had accused the residents of harboring criminals. The threats come in other forms too, including gifts or bribes to buy off residents and divide the members of the quilombo. Their land is squeezed in the middle of a high-end residential neighborhood, which has also encroached onto their territory.

Freed slaves left alone

Many see Brazil's quilombos as relics of the past — the remnants of the legacy of the great Palmares Quilombo, which housed thousands of runaway slaves in the 17th century in the present-day northeastern state of Alagoas.

Slavery left a particularly bloody mark on Brazil. Over three centuries, five million Africans were ripped from their homes and carried across the ocean to be sold as slaves here. The country was the last to abolish slavery in 1888. Even then, indifference from authorities left recently freed slaves to fend for themselves. It created a huge social gap between white and black communities that still exists today. The widespread myth of racial democracy is just that – a myth.

Recently, quilombos have become a way for black communities to acquire a form of reparations for the legacy of slavery. According to the Palmares Cultural Foundation, which certifies quilombos, there are now more than 3,000 across the country. Only 220 have received land titles.

But all of them are under threat from a Supreme Court case, which could invalidate the right to land for quilombos across the country, and even rescind land titles already issued to quilombo communities.

On Thursday, the Supreme Court is expected to rule on the constitutionality of a 2003 decree by former leftist president Luiz Inacio Lula da Silva that gave Brazil's National Institute for Colonization and Agrarian Reform (INCRA) the power to award quilombos land titles, based on their rights under the 1988 constitution.

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The right-wing Democratas party that filed the lawsuit against the decree argues that only territories recognized as quilombos at the time of the 1988 constitution should be eligible for land titles. Many black communities that now identify as quilombos didn't at the time or don't have documents to prove it.

"If the Supreme Court rules the decree unconstitutional, it will be devastating," says Onir Araujo, the lawyer for the six urban quilombos in Porto Alegre. "Devastating for all of the communities, and it will directly impact almost 1 million quilombo members across the country."

Every day discrimination

This is one of three high-profile cases over land rights for indigenous or black communities that have recently reached the Supreme Court. They have come amid the growing influence of large landowners and big business under the government of President Michel Temer, and a wave of attacks on LGBT, black and indigenous communities.

"The police kill someone black every day. Every day, we are being discriminated against. Every day we have to defend ourselves," says Jamaica Machado, a leader of the 300-family Machado Quilombo in Porto Alegre. "My son is six years old. And I have to teach him — just like my mother and grandmother taught me — to fight the prejudice and these things that the government is doing to take us down and oppress us."

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According to the latest figures, nearly two-thirds of the country's unemployed are black. Seventy percent of the victims of Brazil's sky-high murder rate are also black. President Temer has gone out of his way to sidestep the issue, eliminating the federal government's secretariat for racial equality and pushing to end affirmative action at universities.

In December, Machado and dozens of quilombo members rallied against the ongoing racism and the impending Supreme Court case.

"We're done with love. This is going to become Palmares," they chanted, referencing how members of the historic Palmares Quilombo had fought with their lives against the colonial military forces.

It was one of several such actions in recent months. Quilombo members are planning to hold vigils at federal tribunals across the country to accompany the Supreme Court deliberations on Thursday. For them, the court is ruling over not just a question of their land, but a question of their very existence.

"We don't exist if we don't have our land. If we don't have a place to practice our culture and our history," says Tamirez Diaz, a student at the state federal university, who is studying law so she can defend quilombo rights.

It is also a question of the legacy of slavery and racism in Brazil. Something that quilombo communities have no choice but to continue to fight across the country.