The Standing Rock Sioux Tribe’s historic battle to stop the Dakota Access pipeline has attracted international attention, galvanizing public discussion about environmental justice and Native American rights. Earlier this month, after the company in charge of the pipeline callously destroyed newly discovered burial grounds and ancient sites that stood in its path, I wrote that the standoff was “a fight about whose culture matters.”

Today, some 50 museum directors from across the country—and more than 1,000 archaeologists, anthropologists, historians, and museum workers of all kinds—have signed an open letter with a message of solidarity.

“We stand with the Standing Rock Sioux Tribe and affirm their treaty rights, tribal sovereignty, and the protection of their lands, waters, cultural and sacred sites,” it reads, in part, “and we stand with all those attempting to prevent further irreparable losses.”

Among the notable figures whose names are in the letter:

—Richard Lariviere, president and CEO of the Field Museum in Chicago

—Brenda Toineeta Pipestem, chair of the board of trustees of the Smithsonian National Museum of the American Indian

—Suzan Shown Harjo, a 2014 recipient of the Presidential Medal of Freedom for her work preserving Native American culture

—Anne Pasternak, the director of the Brooklyn Museum

—Laura Raicovich, director of the Queens Museum

I reached out to Patsy Phillips, director of the IAIA Museum of Contemporary Native Arts in Santa Fe, about why she had added her name to the open letter. Here is what she wrote:

I’m passionate about supporting Standing Rock in their stand for the protection of the land and water that supports them and their community, and their fight against the corporate interest that threaten their lifestyle and their very existence; however, I’m particularly appalled by the desecration of the graves that has happened recently. Bulldozing a cemetery is unacceptable no matter who it belongs to. It is intolerable and unethical in any community. Indians have not been treated respectfully since before colonization. Today, indigenous people from all over the world are coming together to stand up for our rights and to rewrite our future. This latest gross injustice of disrespecting Natives will not be tolerated. It makes me happy to see so many different tribes and communities of Natives assemble in support of the Standing Rock community, and although I cannot physically be present in North Dakota, I am there in prayer and spirit.

Kathryn Bunn-Marcuse, director of the Bill Holm Center for the Study of Northwest Native Art at the Burke Museum in Seattle, offered this:

I cannot fathom how anyone (or any company) could willfully destroy irreplaceable historical sites or artifacts, without permission or consultation, to gain an economic advantage. As an historian and museum professional, I cannot in good conscience watch in silence while others flout the law to irrevocably rend the fabric of history and the health of the land. Would we merely shrug at the intentional midnight bulldozing of an historic town cemetery? I think not. This is no different.

The letter was initiated by the Natural History Museum, a project of the New York-based art collective Not An Alternative, which has sought to politicize science and natural history museums around issues of climate change.

Beka Economopoulos, a member of Not An Alternative, said that the letter took on a life of its own almost from the moment it was posted to the Facebook page of the Natural History Museum.

“From there it quickly snowballed—hundreds of signatures in the first 24 hours,” Economopoulos wrote. “There were 40-plus people in the Google doc at a time, sometimes several signatures a minute.”

Support from cultural leaders continues to build. Those interested in adding their voices can write to info[at]thenaturalhistorymuseum.org.

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