ALBUQUERQUE – A long-lost original copy of a historic treaty signed in 1868 by leaders of one of the nation’s largest American Indian tribes and the U.S. government will go on display later this year as the Navajo Nation commemorates a dark, but significant chapter of history.

Navajo Vice President Jonathan Nez and other tribal officials gathered Tuesday in Albuquerque to detail some of the events that will mark the signing of the treaty 150 years ago.

That treaty is what cleared the way for tribal members to return to their homeland in the heart of the American Southwest after being rounded up years earlier by the U.S. cavalry and forced to make an arduous and deadly trek hundreds of miles to a camp in eastern New Mexico.

Nez recounted the hardships of what came to be known as the Long Walk, saying many Navajos died along the route to Bosque Redondo. He also talked about those who stayed behind and hid in canyons and on mesa tops, often foregoing the warmth of a fire to avoid capture.

“We want our younger generation to know about our history,” Nez told a room packed with tribal officials and reporters.

He also talked about problems facing tribal communities, from suicide to alcoholism, drug addiction and violence. He said he wants to tap into the resilience of those Navajo ancestors who endured the hardships of the 1800s.

“What this will do is inspire, encourage our people out there that they can’t give up, to jump back up, dust themselves off and to fight even harder than ever before for what they believe in,” Nez said.

Navajo President Russell Begaye has said this year’s commemoration is also about telling the story of the Long Walk, the signing of the treaty and the return home from the perspective of Native Americans. He and other tribal officials say one goal is to address what they called a “legacy of misrepresentation” that has stemmed from that era.

Before research and planning began for this year’s events, there were only two known copies of the historic treaty. The whereabouts of one is now a mystery and the other has been kept by the National Archives and Records Administration.

The third copy turned up only recently when the relatives of a peace commissioner who was involved in the negotiation and signing of the treaty in 1868 found the document in a trunk in the family attic.

It was rolled up and bound with the original but faded ribbon. It was in pristine condition along with notes and other documents that historians hope might fill in some of the blanks from that time.

Pages of that copy will be on display starting in June at the Bosque Redondo Memorial near Fort Sumner, New Mexico.

The National Archives is partnering with the Navajo Nation to display the other original copy at the Navajo Nation Museum in Window Rock, Arizona, for the month of June.

It took more than two years of planning to make the exhibition possible as this marks only the second time an original treaty has gone back to a homeland.

Museum director Manny Wheeler said the treaty is more than just a document to the Navajo people.

“When I saw the document and I saw the marks of all of our leaders on that paper, it is a powerful thing and it is very much so opening up dialogue among all Navajos about who we are, where we’ve come from and where we’re going,” Wheeler said.

Wheeler suggested that as much as the document was key to the Navajos’ past, it also has the power to change the future by awaking tribal members to the importance of preserving their culture and language.

The leaders of the Navajo Nation’s three branches of government signed a proclamation earlier this year declaring 2018 as the year of the treaty, and the tribe launched a website .

The commemoration also includes a day of prayer across the Navajo Nation, cultural nights, tours of the tribal council chambers and a run that will span more than 400 miles (644 kilometers) from Fort Sumner to the Navajo capital.