The Indian Land Tenure Foundation president Cris Stainbrook told The Associated Press that the tribes raised enough money to purchase the land from its current owners. The foundation was one of several groups and organizations leading the effort to buy the land.
Stainbrook said the deal should be finalized yet Friday, which was the deadline for the tribes to raise the money.
The land, known as Pe' Sla, went up for sale after being privately owned. Members of the Great Sioux Nation have been allowed to gather there every year to perform rituals. The site plays a key role in the tribes' creation story, and members fear new owners would develop it.
"This marks the culmination of four months of a worldwide outpouring of support for the protection of Pe' Sla. The Great Sioux Nation came together to show the world it is paramount for human beings to respect our living mother earth and sacred sites," Standing Rock Sioux tribal member Chase Iron Eyes said in a statement. Iron Eyes' company, Last Real Indians, helped raised more than $900,000 for the purchase through online donations.
Earlier this year, landowners Leonard and Margaret Reynolds canceled a public auction of the property after tribal members expressed outrage. The Reynolds' then accepted the tribes' bid to purchase the land for $9 million, should they raise enough money by Nov. 30.
The couple has repeatedly said they will not speak publicly about the land sale.
The fundraising effort drew support from several celebrities. P. Diddy tweeted about as did Bette Midler, who also donated. Midler said she was "happy and proud" to have helped out with the purchase.
"I've been talking about it to my friends, tweeting to the world and donating through my foundation because I think it's important for the soul of our nation," she said in a statement Friday.
Actor Ezra Miller, who appeared in the recently released film "The Perks of Being a Wallflower," and music producer Sol Guy flew to South Dakota last month to film a nine-minute documentary-style video about the land that was used as part of an online campaign to raise funds.
"I think this represents a massive shift for people standing up for what they believe in and the people who are originally from this land. We have a lot to learn and we as a community our stronger together. It's super inspiring," said Sol Guy, whose TV show "4Real" on MTV Canada and the National Geographic Channel takes celebrities to places like Peru and the Amazon.
The fundraising effort has been a monumental and controversial undertaking for the Sioux tribes. An 1868 treaty set aside the Black Hills and other land for the Sioux, but Congress passed a law in 1877 seizing the land following the discovery of gold in western South Dakota.
A 1980 U.S. Supreme Court ruling awarded more than $100 million to the Sioux tribes for the Black Hills, but the tribes have refused to accept the money, saying the land has never been for sale. There are Sioux tribes in the Dakotas, Minnesota, Montana, Nebraska and Canada.
Some members of the Sioux tribes didn't agree with trying to purchase the land. Bryan Brewer, president-elect of the Oglala Sioux Tribe, said his tribe did not allocate any money to the land purchase.
"I'm still against buying something we own, but I'm thrilled the tribes' are buying it. I'm very happy about it," he said.
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