Native American tribes from the United States and Canada have come together to sign a historic treaty that promises to bring the iconic bison back to its original stomping grounds in Rocky Mountain and Great Plains regions.

The treaty, aptly named the "Northern Tribes Buffalo treaty," is the first Native American treaty signed in more than 150 years. It establishes an intertribal alliance between US Tribes and Canadian First Nations so that they can pool their efforts towards the goal of seeing the American buffalo (bison) populations restored on reserves and co-managed lands.

Garrit Voggesser, National Wildlife Federation National Director of Tribal Partnerships said he was encouraged by this action. Collectively, the groups will be best prepared to aid bison, with about 6.3 million acres of grassland - about three times the size of Yellowstone National Park - at their disposal to establish restoration habitats.

"Tribes have managed bison herds for years and worked collaboratively to restore wild bison to the Plains," he said in a statement.

"Tribal leadership can not only bring bison back to tribal lands, but can also foster bison restoration to large public landscapes across the West,' he added. "This treaty will foster and expand the process of restoring a vital part of the prairie ecosystem and crucial part of tribal culture and history."

Eleven tribes in all signed the treaty, pledging to "strengthen and renew ancient cultural and spiritual relationships with buffalo and grasslands in the Northern Great Plains."

Thanks to an immense restoration effort that began in the early 1900s, there are hundreds-of-thousands of bison in North America today. However, most of these animals live as semi-domesticated herds on private land or in zoos. This new initiative aims to brings bison back into the wild.

This is largely "an endeavor on the part of a large group of traditional elders to steer the younger generation back to a path of ecological balance," Leroy Little Bear of the Blood Tribe in Alberta explained. "Sustainability, leaving the land as pristine as possible, and having humans fit themselves into the ecological balance are fundamental to the life-ways of Indian peoples. But the buffalo is a major player in this ecological scenario. The near extinction of the buffalo left a major gap. The treaty on buffalo restoration aims to begin to fill that gap and once again partner with the buffalo to bring about cultural and ecological balance."